1
|
Welch AA, Farahani RA, Egan AM, Laurenti MC, Zeini M, Vella M, Bailey KR, Cobelli C, Dalla Man C, Matveyenko A, Vella A. Glucagon-like peptide-1 receptor blockade impairs islet secretion and glucose metabolism in humans. J Clin Invest 2023; 133:e173495. [PMID: 37751301 PMCID: PMC10645389 DOI: 10.1172/jci173495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 09/12/2023] [Indexed: 09/27/2023] Open
Abstract
BACKGROUNDProglucagon can be processed to glucagon-like peptide1 (GLP-1) within the islet, but its contribution to islet function in humans remains unknown. We sought to understand whether pancreatic GLP-1 alters islet function in humans and whether this is affected by type 2 diabetes.METHODSWe therefore studied individuals with and without type 2 diabetes on two occasions in random order. On one occasion, exendin 9-39, a competitive antagonist of the GLP-1 Receptor (GLP1R), was infused, while on the other, saline was infused. The tracer dilution technique ([3-3H] glucose) was used to measure glucose turnover during fasting and during a hyperglycemic clamp.RESULTSExendin 9-39 increased fasting glucose concentrations; fasting islet hormone concentrations were unchanged, but inappropriate for the higher fasting glucose observed. In people with type 2 diabetes, fasting glucagon concentrations were markedly elevated and persisted despite hyperglycemia. This impaired suppression of endogenous glucose production by hyperglycemia.CONCLUSIONThese data show that GLP1R blockade impairs islet function, implying that intra-islet GLP1R activation alters islet responses to glucose and does so to a greater degree in people with type 2 diabetes.TRIAL REGISTRATIONThis study was registered at ClinicalTrials.gov NCT04466618.FUNDINGThe study was primarily funded by NIH NIDDK DK126206. AV is supported by DK78646, DK116231 and DK126206. CDM was supported by MIUR (Italian Minister for Education) under the initiative "Departments of Excellence" (Law 232/2016).
Collapse
Affiliation(s)
- Andrew A. Welch
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Rahele A. Farahani
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Aoife M. Egan
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Marcello C. Laurenti
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Maya Zeini
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Max Vella
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Kent R. Bailey
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, Minnesota, USA
| | | | - Chiara Dalla Man
- Department of Information Engineering, University of Padova, Padova, Italy
| | - Aleksey Matveyenko
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
| | - Adrian Vella
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| |
Collapse
|
2
|
Visentin R, Brodersen K, Richelsen B, Møller N, Dalla Man C, Pedersen AK, Abrahamsen J, Holst JJ, Nielsen MF. Increased Insulin Secretion and Glucose Effectiveness in Obese Patients with Type 2 Diabetes following Bariatric Surgery. J Diabetes Res 2023; 2023:7127426. [PMID: 38020201 PMCID: PMC10663093 DOI: 10.1155/2023/7127426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 10/24/2023] [Accepted: 10/27/2023] [Indexed: 12/01/2023] Open
Abstract
Background β-cell dysfunction and insulin resistance are the main mechanisms causing glucose intolerance in type 2 diabetes (T2D). Bariatric surgeries, i.e., sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB), are procedures both known to induce weight loss, increase insulin action, and enhance β-cell function, but hepatic insulin extraction and glucose effectiveness may also play a role. Methods To determine the contribution of these regulators on glucose tolerance after bariatric surgery, an oral glucose tolerance test (OGTT) was performed before and 2 months after surgery in 9 RYGB and 7 SG subjects. Eight healthy subjects served as metabolic controls. Plasma glucose, insulin, C-peptide, GLP-1, and GIP were measured during each OGTT. Insulin sensitivity and secretion, glucose effectiveness, and glucose rate of appearance were determined via oral minimal models. Results RYGB and SG resulted in similar weight reductions (13%, RYGB (p < 0.01); 14%, SG (p < 0.05)). Two months after surgery, insulin secretion (p < 0.05) and glucose effectiveness both improved equally in the two groups (11%, RYGB (p < 0.01); 8%, SG (p > 0.05)), whereas insulin sensitivity remained virtually unaltered. Bariatric surgery resulted in a comparable increase in the GLP-1 response during the OGTT, whereas GIP concentrations remained unaltered. Following surgery, oral glucose intake resulted in a comparable increase in hepatic insulin extraction, the response in both RYGB and SG patients significantly exceeding the response observed in the control subjects. Conclusions These results demonstrate that the early improvement in glucose tolerance in obese T2D after RYGB and SG surgeries is attributable mainly to increased insulin secretion and glucose effectiveness, while insulin sensitivity seems to play only a minor role. This trial is registered with NCT02713555.
Collapse
Affiliation(s)
- Roberto Visentin
- Department of Information Engineering, University of Padova, Padova, Italy
| | | | - Bjørn Richelsen
- Steno Diabetes Center Aarhus, Aarhus University Hospital & Clinical Medicine, Aarhus University, Denmark
| | - Niels Møller
- Steno Diabetes Center Aarhus, Aarhus University Hospital & Clinical Medicine, Aarhus University, Denmark
| | - Chiara Dalla Man
- Department of Information Engineering, University of Padova, Padova, Italy
| | | | - Jan Abrahamsen
- Department of Radiology, Viborg General Hospital, Denmark
| | - Jens Juul Holst
- Novo Nordisk Foundation, Center of Basic Metabolic Research and Department of Biomedical Sciences, The Panum Institute, University of Copenhagen, Denmark
| | | |
Collapse
|
3
|
O'Donovan SD, Erdős B, Jacobs DM, Wanders AJ, Thomas EL, Bell JD, Rundle M, Frost G, Arts ICW, Afman LA, van Riel NAW. Quantifying the contribution of triglycerides to metabolic resilience through the mixed meal model. iScience 2022; 25:105206. [PMID: 36281448 DOI: 10.1016/j.isci.2022.105206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 09/01/2022] [Accepted: 09/22/2022] [Indexed: 11/26/2022] Open
Abstract
Despite the pivotal role played by elevated circulating triglyceride levels in the pathophysiology of cardio-metabolic diseases many of the indices used to quantify metabolic health focus on deviations in glucose and insulin alone. We present the Mixed Meal Model, a computational model describing the systemic interplay between triglycerides, free fatty acids, glucose, and insulin. We show that the Mixed Meal Model can capture deviations in the post-meal excursions of plasma glucose, insulin, and triglyceride that are indicative of features of metabolic resilience; quantifying insulin resistance and liver fat; validated by comparison to gold-standard measures. We also demonstrate that the Mixed Meal Model is generalizable, applying it to meals with diverse macro-nutrient compositions. In this way, by coupling triglycerides to the glucose-insulin system the Mixed Meal Model provides a more holistic assessment of metabolic resilience from meal response data, quantifying pre-clinical metabolic deteriorations that drive disease development in overweight and obesity.
Collapse
Affiliation(s)
- Shauna D O'Donovan
- Division of Human Nutrition and Health, Wageningen University, Wageningen, the Netherlands.,Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands.,Eindhoven Artifical Intelligence Systems Institute (EAISI), Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Balázs Erdős
- Maastricht Centre for Systems Biology (MaCSBio), Maastricht University, Maastricht, the Netherlands
| | - Doris M Jacobs
- Unilever Global Food Innovation Centre, Bronland 14, 6708WH Wageningen, the Netherlands
| | - Anne J Wanders
- Unilever Global Food Innovation Centre, Bronland 14, 6708WH Wageningen, the Netherlands
| | - E Louise Thomas
- Research Center for Optimal Health, School of Life Sciences, University of Westminster, London, UK
| | - Jimmy D Bell
- Research Center for Optimal Health, School of Life Sciences, University of Westminster, London, UK
| | - Milena Rundle
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Imperial College London, London, UK
| | - Gary Frost
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Imperial College London, London, UK
| | - Ilja C W Arts
- Maastricht Centre for Systems Biology (MaCSBio), Maastricht University, Maastricht, the Netherlands
| | - Lydia A Afman
- Division of Human Nutrition and Health, Wageningen University, Wageningen, the Netherlands
| | - Natal A W van Riel
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands.,Eindhoven Artifical Intelligence Systems Institute (EAISI), Eindhoven University of Technology, Eindhoven, the Netherlands
| |
Collapse
|
4
|
Zhou J, Liu X, Chou OHI, Li L, Lee S, Wong WT, Zhang Q, Chang C, Liu T, Tse G, Jing F, Cheung BMY. Lower risk of gout in sodium glucose cotransporter 2 (SGLT2) inhibitors versus dipeptidyl peptidase-4 (DPP4) inhibitors in type-2 diabetes. Rheumatology (Oxford) 2022; 62:1501-1510. [PMID: 36066415 DOI: 10.1093/rheumatology/keac509] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 07/25/2022] [Accepted: 08/13/2022] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The effects of sodium-glucose cotransporter 2 inhibitors (SGLT2I) vs dipeptidyl peptidase-4 inhibitors (DPP4I) on the risk of new-onset gout remains unknown. This study aims to compare the effects of SGLT2I against DPP4I on gout risks. METHODS This was a retrospective population-based cohort study of patients with type-2 diabetes mellitus treated with SGLT2I or DPP4I between January 1st, 2015 and December 31st, 2020 in Hong Kong. The study outcomes are new-onset gout and all-cause mortality. Propensity score matching (1:1 ratio) between SGLT2I and DPP4I was performed. Univariable and multivariable Cox regression analysis models were conducted. Competing risks models and multiple approaches based on the propensity score were applied. RESULTS This study included 43201 patients (median age: 63.23 years old [Interquantile range, IQR]: 55.21-71.95, 53.74% males; SGLTI group: n = 16144; DPP4I group: n = 27057) with a median follow-up of 5.59 years (IQR: 5.27-5.81 years) since initial drug exposure. The incidence rate of developing gout (Incidence rate [IR]: 2.5; 95% CI: 2.2-2.9) among SGLT2I users was significantly lower than DPP4I users (IR: 5.2; 95% CI: 4.8-5.8). SGLT2 was associated with 51% lower risks of gout (HR: 0.49; 95% CI: 0.42-0.58; P-value < 0.0001) and 51% lower risks of all-cause mortality (HR: 0.49; 95% CI: 0.42-0.58; P-value < 0.0001) after adjusting for significant demographics, past comorbidities, medications, and laboratory results. The results remained consistent on competing risk and other propensity score approaches. CONCLUSIONS SGLT2I use was associated with lower risks of new gout diagnosis compared with DPP4I use.
Collapse
Affiliation(s)
- Jiandong Zhou
- Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom.,Diabetes Research Unit, Cardiovascular Analytics Group, Hong Kong, China, UK Collaboration
| | - Xuejin Liu
- School of Educational Science, Kaili University, Kaili, Guizhou, China
| | - Oscar Hou-In Chou
- School of Educational Science, Kaili University, Kaili, Guizhou, China.,Division of Clinical Pharmacology, Department of Medicine, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, China
| | - Lifang Li
- Department of Biostatistics & Health Informatics, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Sharen Lee
- Diabetes Research Unit, Cardiovascular Analytics Group, Hong Kong, China, UK Collaboration
| | - Wing Tak Wong
- School of Life Sciences, Chinese University of Hong Kong, Hong Kong, China
| | - Qingpeng Zhang
- School of Data Science, City University of Hong Kong, Hong Kong, China
| | - Carlin Chang
- Department of Medicine, Queen Mary Hospital, Hong Kong, China
| | - Tong Liu
- Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, 300211, China
| | - Gary Tse
- Diabetes Research Unit, Cardiovascular Analytics Group, Hong Kong, China, UK Collaboration.,Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, 300211, China.,Kent and Medway Medical School, Canterbury, United Kingdom
| | - Fengshi Jing
- Institute for Artificial Intelligence, Guangdong Second Provincial General Hospital, Guangzhou, China.,The University of North Carolina at Chapel Hill Project-China, Guangzhou, China
| | - Bernard Man Yung Cheung
- Division of Clinical Pharmacology, Department of Medicine, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, China
| |
Collapse
|
5
|
Cobelli C, Dalla Man C. Minimal and Maximal Models to Quantitate Glucose Metabolism: Tools to Measure, to Simulate and to Run in Silico Clinical Trials. J Diabetes Sci Technol 2022; 16:1270-1298. [PMID: 34032128 PMCID: PMC9445339 DOI: 10.1177/19322968211015268] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Several models have been proposed to describe the glucose system at whole-body, organ/tissue and cellular level, designed to measure non-accessible parameters (minimal models), to simulate system behavior and run in silico clinical trials (maximal models). Here, we will review the authors' work, by putting it into a concise historical background. We will discuss first the parametric portrait provided by the oral minimal models-building on the classical intravenous glucose tolerance test minimal models-to measure otherwise non-accessible key parameters like insulin sensitivity and beta-cell responsivity from a physiological oral test, the mixed meal or the oral glucose tolerance tests, and what can be gained by adding a tracer to the oral glucose dose. These models were used in various pathophysiological studies, which we will briefly review. A deeper understanding of insulin sensitivity can be gained by measuring insulin action in the skeletal muscle. This requires the use of isotopic tracers: both the classical multiple-tracer dilution and the positron emission tomography techniques are discussed, which quantitate the effect of insulin on the individual steps of glucose metabolism, that is, bidirectional transport plasma-interstitium, and phosphorylation. Finally, we will present a cellular model of insulin secretion that, using a multiscale modeling approach, highlights the relations between minimal model indices and subcellular secretory events. In terms of maximal models, we will move from a parametric to a flux portrait of the system by discussing the triple tracer meal protocol implemented with the tracer-to-tracee clamp technique. This allows to arrive at quasi-model independent measurement of glucose rate of appearance (Ra), endogenous glucose production (EGP), and glucose rate of disappearance (Rd). Both the fast absorbing simple carbs and the slow absorbing complex carbs are discussed. This rich data base has allowed us to build the UVA/Padova Type 1 diabetes and the Padova Type 2 diabetes large scale simulators. In particular, the UVA/Padova Type 1 simulator proved to be a very useful tool to safely and effectively test in silico closed-loop control algorithms for an artificial pancreas (AP). This was the first and unique simulator of the glucose system accepted by the U.S. Food and Drug Administration as a substitute to animal trials for in silico testing AP algorithms. Recent uses of the simulator have looked at glucose sensors for non-adjunctive use and new insulin molecules.
Collapse
Affiliation(s)
- Claudio Cobelli
- Department of Woman and Child’s Health University of Padova, Padova, Italy
- Claudio Cobelli, PhD, Department of Woman and Child’s Health, University of Padova, Via N. Giustiniani, 3, Padova 35128, Italy.
| | - Chiara Dalla Man
- Department of Information Engineering, University of Padova, Padova, Italy
| |
Collapse
|
6
|
Visentin R, Cobelli C, Dalla Man C. A software interface for in silico testing of type 2 diabetes treatments. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2022; 223:106973. [PMID: 35792365 DOI: 10.1016/j.cmpb.2022.106973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 06/09/2022] [Accepted: 06/21/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND AND OBJECTIVE The increasing incidence of diabetes continuously stimulates the research on new antidiabetic drugs. Computer simulation can save time and costs, alleviating the need of animal trials and providing useful information for optimal experiment design and drug dosing. We recently presented a type 2 diabetes (T2D) simulator as tool for in silico testing of new molecules and guiding treatment optimization. Here we present a user-friendly interface aimed to increase the usability of the simulator. METHOD The simulator, based on a large-scale glucose, insulin, and C-peptide model and equipped with 100 virtual subjects well describing system dynamics in a real T2D population, is extended to incorporate pharmacokinetics/pharmacodynamics (PK/PD) of a drug of interest. A graphical interface is developed on top of the simulator, allowing an easy design of in silico experiments: specifically, it is possible to select the population size to test, design the experiment (crossover or parallel), its duration and the sampling grid, choose glucose and insulin doses, and define treatment PK/PD and dose administered. The simulator also provides the outcome metrics requested by the user, and performs statistical comparisons among treatments and/or placebo. RESULTS To illustrate the potential of the simulator, we provided a case study using metformin and liraglutide. Literature-based PK/PD models of metformin and liraglutide have been incorporated in the simulator, by modulating key drug-sensitive model parameters. An in silico placebo-controlled trial has been done by simulating a three-arm meal tolerance test with subjects receiving placebo, metformin 850 mg, liraglutide 1.80 mg, respectively. The obtained results are in agreement with the clinical evidences, in terms of main glucose, insulin, and C-peptide outcome metrics. CONCLUSIONS We developed a user-friendly software interface for the T2D simulator to support the design and test of new antidiabetic drugs and treatments. This increases the simulator usability, making it suitable also for users who have low experience with computer programming.
Collapse
Affiliation(s)
- Roberto Visentin
- Department of Information Engineering, University of Padova, Padova, Italy
| | - Claudio Cobelli
- Department of Woman and Child's Health, University of Padova, Padova, Italy
| | - Chiara Dalla Man
- Department of Information Engineering, University of Padova, Padova, Italy.
| |
Collapse
|
7
|
Hmood A, Almasoody M, Al-Jameel HH. Contrasting Three Non-hypoglycemic Antidiabetic Drug Effects on Glycemic Control in Newly Diagnosed Type II Diabetes Mellitus: An Experimental Study. Open Access Maced J Med Sci 2022. [DOI: 10.3889/oamjms.2022.8631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
BACKGROUND: Diabetes mellitus (DM) type 2 is the most public chronic, metabolic illness whose prevalence is quickly becoming high international. Insulin resistance, the essential metabolic problem leads to the development of DM type 2, is seen in about 90% of patients.
AIM: The study’s aim was to compare the efficacy of three antidiabetic drugs on glycated hemoglobin.
METHOD: A cross-sectional comparative study for newly diagnosed type II diabetic patients were assigned randomly into one of three conditions: Group I: Metformin consuming patients, Group II: Pioglitazone consuming patients, and Group III: Vildagliptin consuming patients. All patients were newly diagnosed. For all of them, baseline glycated hemoglobin was requested. After that, random assignment was carried out. After 3 months, glycated hemoglobin was checked and compared.
RESULTS: Participants were distributed randomly into 27.9% metformin taking participants, 31.1% pioglitazone taking, and 41% vildagliptin taking patient. Findings suggested significant difference between Groups I and III (p =). Likewise, significant difference was seen between Groups II and III (p =). However, Groups I and II have comparable effects (p =). Indeed, all groups had shown significant efficacy on HbA1c.
CONCLUSION: Metformin, pioglitazone, and vildagliptin had shown significant impact on HbA1c with variable degree: Metformin and pioglitazone had shown comparably similar efficacy that was exerted more significant impact on HbA1c than vildagliptin does.
Collapse
|
8
|
Rizvi AA, Abbas M, Verma S, Verma S, Khan A, Raza ST, Mahdi F. Determinants in Tailoring Antidiabetic Therapies: A Personalized Approach. Glob Med Genet 2022; 9:63-71. [PMID: 35707783 PMCID: PMC9192178 DOI: 10.1055/s-0041-1741109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 11/20/2021] [Indexed: 11/02/2022] Open
Abstract
AbstractDiabetes has become a pandemic as the number of diabetic people continues to rise globally. Being a heterogeneous disease, it has different manifestations and associated complications in different individuals like diabetic nephropathy, neuropathy, retinopathy, and others. With the advent of science and technology, this era desperately requires increasing the pace of embracing precision medicine and tailoring of drug treatment based on the genetic composition of individuals. It has been previously established that response to antidiabetic drugs, like biguanides, sulfonylureas, dipeptidyl peptidase-4 (DPP-4) inhibitors, glucagon-like peptide 1 (GLP-1) agonists, and others, depending on variations in their transporter genes, metabolizing genes, genes involved in their action, etc. Responsiveness of these drugs also relies on epigenetic factors, including histone modifications, miRNAs, and DNA methylation, as well as environmental factors and the lifestyle of an individual. For precision medicine to make its way into clinical procedures and come into execution, all these factors must be reckoned with. This review provides an insight into several factors oscillating around the idea of precision medicine in type-2 diabetes mellitus.
Collapse
Affiliation(s)
- Aliya A. Rizvi
- Department of Personalized and Molecular Medicine, Era University, Lucknow, Uttar Pradesh, India
| | - Mohammad Abbas
- Department of Personalized and Molecular Medicine, Era University, Lucknow, Uttar Pradesh, India
| | - Sushma Verma
- Department of Personalized and Molecular Medicine, Era University, Lucknow, Uttar Pradesh, India
| | - Shrikant Verma
- Department of Personalized and Molecular Medicine, Era University, Lucknow, Uttar Pradesh, India
| | - Almas Khan
- Department of Personalized and Molecular Medicine, Era University, Lucknow, Uttar Pradesh, India
| | - Syed T. Raza
- Department of Biochemistry, Era University, Lucknow Medical College and Hospital, Lucknow, Uttar Pradesh, India
| | - Farzana Mahdi
- Department of Personalized and Molecular Medicine, Era University, Lucknow, Uttar Pradesh, India
| |
Collapse
|
9
|
Ahrén B, Pacini G. Glucose effectiveness: Lessons from studies on insulin-independent glucose clearance in mice. J Diabetes Investig 2021; 12:675-685. [PMID: 33098240 PMCID: PMC8088998 DOI: 10.1111/jdi.13446] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 10/15/2020] [Accepted: 10/19/2020] [Indexed: 01/07/2023] Open
Abstract
Besides insulin-mediated transport of glucose into the cells, an important role is also played by the non-insulin-mediated transport. This latter process is called glucose effectiveness (acronym SG ), which is estimated by modeling of glucose and insulin data after an intravenous glucose administration, and accounts for ≈70% of glucose disposal. This review summarizes studies on SG , mainly in humans and rodents with focus on results achieved in model experiments in mice. In humans, SG is reduced in type 2 diabetes, in obesity, in liver cirrhosis and in some elderly populations. In model experiments in mice, SG is independent from glucose levels, but increases when insulin secretion is stimulated, such as after administration of the incretin hormones, glucagon-like peptide-1 and glucose-dependent insulinotropic polypeptide. SG is reduced in insulin resistance induced by high-fat feeding and by exogenous administration of glucagon. Glucose-dependent (insulin-independent) glucose disposal is therefore important for glucose elimination, and it is also well regulated. It might be of pathophysiological relevance for the development of type 2 diabetes, in particular during insulin resistance, and might also be a target for glucose-reducing therapy. Measuring SG is essentially important when carrying out metabolic studies to understand glucose homeostasis.
Collapse
Affiliation(s)
- Bo Ahrén
- Department of Clinical Sciences LundLund UniversityLundSweden
| | - Giovanni Pacini
- Metabolic UnitInstitute of Neurosciences (IN‐CNR)PadovaItaly
| |
Collapse
|
10
|
Liu X, Liu Y, Liu H, Li H, Yang J, Hu P, Xiao X, Liu D. Dipeptidyl-Peptidase-IV Inhibitors, Imigliptin and Alogliptin, Improve Beta-Cell Function in Type 2 Diabetes. Front Endocrinol (Lausanne) 2021; 12:694390. [PMID: 34616361 PMCID: PMC8488395 DOI: 10.3389/fendo.2021.694390] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 08/23/2021] [Indexed: 11/13/2022] Open
Abstract
OBJECTS Imigliptin is a novel dipeptidyl peptidase-4 inhibitor. In the present study, we aimed to evaluate the effects of imigliptin and alogliptin on insulin resistance and beta-cell function in Chinese patients with type-2 diabetes mellitus (T2DM). METHODS A total of 37 Chinese T2DM patients were randomized to receive 25 mg imigliptin, 50 mg imigliptin, placebo, and 25 mg alogliptin (positive drug) for 13 days. Oral glucose tolerance tests were conducted at baseline and on day 13, followed by the oral minimal model (OMM). RESULTS Imigliptin or alogliptin treatment, compared with their baseline or placebo, was associated with higher beta-cell function parameters (φs and φtot) and lower glucose area under the curve (AUC) and postprandial glucose levels. The changes in the AUC for the glucose appearance rate between 0 and 120 min also showed a decrease in imigliptin or alogliptin groups. However, the insulin resistance parameter, fasting glucose, was not changed. For the homeostatic model assessment (HOMA-β and HOMA-IR) parameters or secretory units of islets in transplantation index (SUIT), no statistically significant changes were found both within treatments and between treatments. CONCLUSIONS After 13 days of treatment, imigliptin and alogliptin could decrease glycemic levels by improving beta-cell function. By comparing OMM with HOMA or SUIT results, glucose stimulation might be more sensitive for detecting changes in beta-cell function.
Collapse
Affiliation(s)
- Xu Liu
- Savaid Medical School, University of Chinese Academy of Sciences, Beijing, China
- Drug Clinical Trial Center, Peking University Third Hospital, Beijing, China
| | - Yang Liu
- Clinical Pharmacology Research Center, Peking Union Medical College Hospital and Chinese Academy of Medical Sciences, Beijing, China
- Department of Pharmacology, College of Pharmacy, Inner Mongolia Medical University, Hohhot, China
| | - Hongzhong Liu
- Clinical Pharmacology Research Center, Peking Union Medical College Hospital and Chinese Academy of Medical Sciences, Beijing, China
| | - Haiyan Li
- Drug Clinical Trial Center, Peking University Third Hospital, Beijing, China
- Center of Clinical Medical Research, Institute of Medical Innovation and Research, Peking University Third Hospital, Beijing, China
| | - Jianhong Yang
- Savaid Medical School, University of Chinese Academy of Sciences, Beijing, China
| | - Pei Hu
- Clinical Pharmacology Research Center, Peking Union Medical College Hospital and Chinese Academy of Medical Sciences, Beijing, China
| | - Xinhua Xiao
- Department of Endocrinology, Key Laboratory of Endocrinology of National Health Commission, Peking Union Medical College Hospital and Chinese Academy of Medical Sciences, Beijing, China
| | - Dongyang Liu
- Drug Clinical Trial Center, Peking University Third Hospital, Beijing, China
- Center of Clinical Medical Research, Institute of Medical Innovation and Research, Peking University Third Hospital, Beijing, China
| |
Collapse
|
11
|
Visentin R, Schiavon M, Göbel B, Riz M, Cobelli C, Klabunde T, Dalla Man C. Dual glucagon-like peptide-1 receptor/glucagon receptor agonist SAR425899 improves beta-cell function in type 2 diabetes. Diabetes Obes Metab 2020; 22:640-647. [PMID: 31808298 DOI: 10.1111/dom.13939] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 12/02/2019] [Accepted: 12/02/2019] [Indexed: 12/15/2022]
Abstract
AIM To evaluate the change in insulin sensitivity, β-cell function and glucose absorption after 28 days of treatment with high and low doses of SAR425899, a novel dual glucagon-like peptide-1 receptor/glucagon receptor agonist, versus placebo. MATERIALS AND METHODS Thirty-six overweight to obese subjects with type 2 diabetes were randomized to receive daily subcutaneous administrations of low-dose SAR425899 (0.03, 0.06 and 0.09 mg) and high-dose SAR425899 (0.06, 0.12 and 0.18 mg) or placebo for 28 days; dose escalation occurred after days 7 and 14. Mixed meal tolerance tests were conducted before treatment (day -1) and on days 1 and 28. Oral glucose and C-peptide minimal models were used to quantify metabolic indices of insulin sensitivity, β-cell responsiveness and glucose absorption. RESULTS With low-dose SAR425899, high-dose SAR425899 and placebo, β-cell function from day -1 to day 28 increased by 163%, 95% and 23%, respectively. The change in area under the curve for the rate of meal glucose appearance between 0 and 120 minutes was -32%, -20% and 8%, respectively. CONCLUSIONS After 28 days of treatment, SAR425899 improved postprandial glucose control by significantly enhancing β-cell function and slowing glucose absorption rate.
Collapse
Affiliation(s)
- Roberto Visentin
- Department of Information Engineering, University of Padova, Padova, Italy
| | - Michele Schiavon
- Department of Information Engineering, University of Padova, Padova, Italy
| | - Britta Göbel
- Sanofi-Aventis Deutschland GmbH, Frankfurt am Main, Germany
| | - Michela Riz
- Sanofi-Aventis Deutschland GmbH, Frankfurt am Main, Germany
| | - Claudio Cobelli
- Department of Information Engineering, University of Padova, Padova, Italy
| | | | - Chiara Dalla Man
- Department of Information Engineering, University of Padova, Padova, Italy
| |
Collapse
|
12
|
Identification of osteoclast-osteoblast coupling factors in humans reveals links between bone and energy metabolism. Nat Commun 2020; 11:87. [PMID: 31911667 PMCID: PMC6946812 DOI: 10.1038/s41467-019-14003-6] [Citation(s) in RCA: 109] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 12/09/2019] [Indexed: 01/20/2023] Open
Abstract
Bone remodeling consists of resorption by osteoclasts followed by formation by osteoblasts, and osteoclasts are a source of bone formation-stimulating factors. Here we utilize osteoclast ablation by denosumab (DMAb) and RNA-sequencing of bone biopsies from postmenopausal women to identify osteoclast-secreted factors suppressed by DMAb. Based on these analyses, LIF, CREG2, CST3, CCBE1, and DPP4 are likely osteoclast-derived coupling factors in humans. Given the role of Dipeptidyl Peptidase-4 (DPP4) in glucose homeostasis, we further demonstrate that DMAb-treated participants have a significant reduction in circulating DPP4 and increase in Glucagon-like peptide (GLP)-1 levels as compared to the placebo-treated group, and also that type 2 diabetic patients treated with DMAb show significant reductions in HbA1c as compared to patients treated either with bisphosphonates or calcium and vitamin D. Thus, our results identify several coupling factors in humans and uncover osteoclast-derived DPP4 as a potential link between bone remodeling and energy metabolism. Anti-resorptive bone therapies also inhibit bone formation, as osteoclasts secrete factors that stimulate bone formation by osteoblasts. Here, the authors identify osteoclast-secreted factors that couple bone resorption to bone formation in healthy subjects, and show that osteoclast-derived DPP4 may be a factor coupling bone resorption to energy metabolism.
Collapse
|
13
|
Yaribeygi H, Atkin SL, Sahebkar A. Natural compounds with DPP-4 inhibitory effects: Implications for the treatment of diabetes. J Cell Biochem 2019; 120:10909-10913. [PMID: 30775811 DOI: 10.1002/jcb.28467] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2018] [Accepted: 12/17/2018] [Indexed: 02/06/2023]
Abstract
Dipeptidyl peptidase-4 (DPP-4) inhibitors are antidiabetes agents that decrease blood glucose by preventing the degradation of endogenous glucagon-like peptide-1. The first DPP-4 was sitagliptin followed by several other agents in the class introduced to manage diabetes. Recent studies have suggested that naturally occurring compounds can exert an antidiabetes effect through DPP-4 inhibition. Such compounds may have a place in the treatment of diabetes within the diet; however, while DPP-4 inhibition alone is not associated with hypoglycemia, in combinations with other medication hypoglycemia can result, therefore, it is critical to know what herbal or food-based compounds may have these activities in the management of diabetes patients. In this review, we have outlined the compounds that have DPP-4 inhibition that may have utility in the treatment of diabetes.
Collapse
Affiliation(s)
- Habib Yaribeygi
- Chronic Kidney Disease Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Amirhossein Sahebkar
- Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.,Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran.,School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| |
Collapse
|
14
|
Shah M, Laurenti MC, Dalla Man C, Ma J, Cobelli C, Rizza RA, Vella A. Contribution of endogenous glucagon-like peptide-1 to changes in glucose metabolism and islet function in people with type 2 diabetes four weeks after Roux-en-Y gastric bypass (RYGB). Metabolism 2019; 93:10-17. [PMID: 30586575 PMCID: PMC6401231 DOI: 10.1016/j.metabol.2018.12.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 12/07/2018] [Accepted: 12/20/2018] [Indexed: 01/03/2023]
Abstract
UNLABELLED Glucagon-Like Peptide-1 (GLP-1) is an insulin secretagogue which is elevated after Roux-en-Y Gastric Bypass (RYGB). However, its contribution to glucose metabolism after RYGB remains uncertain. AIMS We tested the hypothesis that GLP-1 lowers postprandial glucose concentrations and improves β-cell function after RYGB. MATERIALS AND METHODS To address these questions we used a labeled mixed meal to assess glucose metabolism and islet function in 12 obese subjects with type 2 diabetes studied before and four weeks after RYGB. During the post-RYGB study subjects were randomly assigned to receive an infusion of either saline or Exendin-9,39 a competitive antagonist of GLP-1 at its receptor. Exendin-9,39 was infused at 300 pmol/kg/min for 6 h. All subjects underwent RYGB for medically-complicated obesity. RESULTS Exendin-9,39 resulted in increased integrated incremental postprandial glucose concentrations (181 ± 154 vs. 582 ± 129 mmol per 6 h, p = 0.02). In contrast, this was unchanged in the presence of saline (275 ± 88 vs. 315 ± 66 mmol per 6 h, p = 0.56) after RYGB. Exendin-9,39 also impaired β-cell responsivity to glucose but did not alter Disposition Index (DI). CONCLUSIONS These data indicate that the elevated GLP-1 concentrations that occur early after RYGB improve postprandial glucose tolerance by enhancing postprandial insulin secretion.
Collapse
Affiliation(s)
- Meera Shah
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA.
| | - Marcello C Laurenti
- Department of Information Engineering, University of Padua, Via Gradenigo 6A, Padua 35131, Italy.
| | - Chiara Dalla Man
- Department of Information Engineering, University of Padua, Via Gradenigo 6A, Padua 35131, Italy.
| | - Jing Ma
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA.
| | - Claudio Cobelli
- Department of Information Engineering, University of Padua, Via Gradenigo 6A, Padua 35131, Italy.
| | - Robert A Rizza
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA.
| | - Adrian Vella
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA.
| |
Collapse
|
15
|
Foley JE, Ahrén B. The Vildagliptin Experience - 25 Years Since the Initiation of the Novartis Glucagon-like Peptide-1 Based Therapy Programme and 10 Years Since the First Vildagliptin Registration. EUROPEAN ENDOCRINOLOGY 2018; 13:56-61. [PMID: 29632608 PMCID: PMC5813465 DOI: 10.17925/ee.2017.13.02.56] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 07/25/2017] [Indexed: 01/14/2023]
Abstract
The discovery of the incretin hormone glucagon like peptide-1 (GLP-1), and its usefulness in the treatment of type 2 diabetes mellitus (T2DM) followed by the finding that dipeptidyl peptidase-4 (DPP-4) inhibition prevents GLP-1 inactivation, led to the discovery of DPP-728. In 1999, studies with DPP-728 established the first proof-of-concept that DPP-4 inhibition improves glycaemic control in patients with T2DM. Further efforts to improve the binding kinetics of DPP-728 resulted in the discovery of vildagliptin (LAF237). In the last 20 years, a plethora of studies conducted by Novartis in collaboration with external investigators has demonstrated the mechanism of action of vildagliptin and its efficacy as monotherapy and as an add-on therapy for patients with T2DM. The studies establish that vildagliptin is a selective DPP-4 inhibitor that blocks GLP-1 and glucose-dependent insulinotropic polypeptide (GIP) inactivation, thereby prolonging their action, resulting in improved glycaemic control. This review aims to discuss the discovery and development of vildagliptin, with an emphasis on mechanism of action and clinical efficacy.
Collapse
Affiliation(s)
- James E Foley
- Novartis Pharmaceuticals Corporation, East Hanover, NJ, US
| | - Bo Ahrén
- Department of Clinical Sciences, Lund University, Lund, Sweden
| |
Collapse
|
16
|
Shankar SS, Shankar RR, Mixson LA, Miller DL, Steinberg HO, Beals CR, Kelley DE. Insulin secretory effect of sitagliptin: assessment with a hyperglycemic clamp combined with a meal challenge. Am J Physiol Endocrinol Metab 2018; 314:E406-E412. [PMID: 29138226 DOI: 10.1152/ajpendo.00238.2017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Sitagliptin, a dipeptidyl peptidase-IV inhibitor (DPP-4), sustains activity of the incretin hormones GLP-1 and GIP and improves hyperglycemia in Type 2 diabetes mellitus (T2DM). It has however proven challenging to quantify the effect of sitagliptin on rates of insulin secretion (ISR) during a prandial challenge. The tight feedback governance of ISR by plasma glucose means that in the face of treatment-related lowering of postprandial glycemia, corresponding stimulation of ISR is lessened. We postulated that sustaining a stable level of moderate hyperglycemia before and during a meal challenge (MC) would be a platform that enables greater clarity to assess the effect of sitagliptin on ISR and an approach that could be valuable to evaluate novel targets that increase insulin secretion directly and by augmenting incretins. A hyperglycemic clamp (HGC) at 160 mg/dl was conducted in 12 healthy volunteers (without diabetes) for 6 h; 3 h into the HGC, MC was administered while maintaining stable hyperglycemia of the HGC for an additional 3 h. Modeling of C-peptide response was used to calculate ISR. In crossover design of three periods (sitagliptin twice and placebo once), the effect of sitagliptin vs. placebo on ISR and the reproducibility of the response to sitagliptin were assessed. Sitagliptin increased ISR compared with placebo by 50% and 20% during the HGC alone and the HGC-MC phases, respectively ( P < 0.001 for both). There was an associated significant treatment-based increase in circulating insulin, as well as active levels of GLP-1. Robust reproducibility of the sitagliptin-mediated ISR response was observed; the intraclass correlation value was 0.94. The findings delineate the effect of sitagliptin to stimulate insulin secretion, and these benchmark data also demonstrate that an HGC-MC can be a useful platform for interrogating therapeutic targets that could potentially modulate ISR via direct action on beta-cells as well as by augmenting release or action of incretins.
Collapse
Affiliation(s)
| | | | - Lori A Mixson
- Merck & Company, Incorporated, Kenilworth, New Jersey
| | | | | | - Chan R Beals
- Merck & Company, Incorporated, Kenilworth, New Jersey
| | | |
Collapse
|
17
|
Bogachus LD, Bellin MD, Vella A, Robertson RP. Deficient Glucagon Response to Hypoglycemia During a Mixed Meal in Total Pancreatectomy/Islet Autotransplantation Recipients. J Clin Endocrinol Metab 2018; 103:1522-1529. [PMID: 29351616 PMCID: PMC6276676 DOI: 10.1210/jc.2017-02182] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 01/12/2018] [Indexed: 12/26/2022]
Abstract
CONTEXT Total pancreatectomy and intrahepatic islet autotransplantation (TP/IAT) is performed to alleviate severe abdominal pain, avoid narcotic use, maintain islet function, and avoid diabetes in patients with chronic pancreatitis. However, many TP/IAT recipients complain of postprandial hypoglycemia. OBJECTIVE This study was designed to discover the mechanisms of this problem. DESIGN Participants consumed a triple-isotope mixed meal. SETTING This study was performed in a hospital research unit. PARTICIPANTS We studied 10 TP/IAT recipients and 10 age- and body mass index-matched control subjects. Seven of 10 recipients had a history of postprandial hypoglycemia. INTERVENTIONS Participants were given a [1-13C]-labeled mixed meal and two tracer infusions ([6,6-2H2]- and [6-3H]-glucose). MAIN OUTCOME MEASURES Glucose kinetics and concentrations of regulatory hormones were determined. RESULTS Immediately after the meal, peak glucose was elevated in recipients compared with control subjects [266 ± 20 mg/dL (14.8 ± 1.1 mmol/L) vs 185 ± 13 mg/dL (10.3 ± 0.7 mmol/L); P = 0.01]. However, mean Δ glucose for TP/IAT recipients between minutes 240 and 360 postprandially was significantly lower than for control subjects (P < 0.05); six of the seven recipients with a history of hypoglycemia experienced abnormally low postprandial Δ glucose. Δ Glucagon remained unchanged (minutes 240 to 360; P = 0.58) in TP/IAT recipients despite abnormal decreases in postprandial glucose. Radioisotopic studies revealed that meal appearance, glucose disappearance, and endogenous glucose production in TP/IAT recipients were not different from control subjects. CONCLUSION Initially high glucose levels followed by hypoglycemia with an absent glucagon response is a mechanistic sequence that contributes to postprandial hypoglycemia after TP/IAT.
Collapse
Affiliation(s)
- Lindsey D Bogachus
- Pacific Northwest Diabetes Research Institute, Seattle, Washington
- Department of Medicine, Division of Metabolism, Endocrinology, and Nutrition,
University of Washington, Seattle, Washington
| | - Melena D Bellin
- Department of Medicine and Pediatrics, Division of Diabetes, Endocrinology, and
Metabolism, University of Minnesota, Minneapolis, Minnesota
| | - Adrian Vella
- Mayo Clinic College of Medicine, Division of Endocrinology, Diabetes, and
Metabolism, Rochester, Minnesota
| | - R Paul Robertson
- Pacific Northwest Diabetes Research Institute, Seattle, Washington
- Department of Medicine, Division of Metabolism, Endocrinology, and Nutrition,
University of Washington, Seattle, Washington
- Department of Medicine and Pediatrics, Division of Diabetes, Endocrinology, and
Metabolism, University of Minnesota, Minneapolis, Minnesota
- Correspondence and Reprint Requests: R. Paul Robertson, MD, Pacific Northwest Diabetes Research Institute, 720
Broadway, Seattle, Washington 98122. E-mail:
| |
Collapse
|
18
|
Varghese RT, Man CD, Laurenti MC, Piccinini F, Sharma A, Shah M, Bailey KR, Rizza RA, Cobelli C, Vella A. Performance of individually measured vs population-based C-peptide kinetics to assess β-cell function in the presence and absence of acute insulin resistance. Diabetes Obes Metab 2018; 20:549-555. [PMID: 28862812 PMCID: PMC5946313 DOI: 10.1111/dom.13106] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 08/22/2017] [Accepted: 08/29/2017] [Indexed: 01/07/2023]
Abstract
AIMS To compare the performance of population-based kinetics with that of directly measured C-peptide kinetics when used to calculate β-cell responsivity indices, and to study people with and without acute insulin resistance to ensure that population-based kinetics apply to all conditions where β-cell function is measured. METHODS Somatostatin was used to inhibit endogenous insulin secretion in 56 people without diabetes. Subsequently, a C-peptide bolus was administered and the changing concentrations were used to calculate individual kinetic measures of C-peptide clearance. In addition, the participants were studied on 2 occasions in random order using an oral glucose tolerance test (OGTT). On one occasion, free fatty acid elevation, to cause insulin resistance, was achieved by infusion of Intralipid + heparin. The Disposition Index (DI) was then estimated by the oral minimal model using either population-based or individual C-peptide kinetics. RESULTS There were marked differences in the exchange variables (k 12 and k 21 ) of the model describing C-peptide kinetics, but smaller differences in the fractional clearance; that is, the irreversible loss from the accessible compartment (k 01 ), obtained from population-based estimates compared with experimental measurement. Because it is predominantly influenced by k 01 , DI estimated using individual kinetics correlated well with DI estimated using population-based kinetics. CONCLUSIONS These data support the use of population-based measures of C-peptide kinetics to estimate β-cell function during an OGTT.
Collapse
Affiliation(s)
- Ron T. Varghese
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic, 200 1 St SW, 5-194 Joseph, Rochester, Minnesota USA
| | - Chiara Dalla Man
- Department of Information Engineering, Universita’ di Padova, Via Gradenigo 6B, Padova, Italy
| | - Marcello C. Laurenti
- Department of Information Engineering, Universita’ di Padova, Via Gradenigo 6B, Padova, Italy
| | - Francesca Piccinini
- Department of Information Engineering, Universita’ di Padova, Via Gradenigo 6B, Padova, Italy
| | - Anu Sharma
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic, 200 1 St SW, 5-194 Joseph, Rochester, Minnesota USA
| | - Meera Shah
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic, 200 1 St SW, 5-194 Joseph, Rochester, Minnesota USA
| | - Kent R. Bailey
- Division of Biomedical Statistics and Informatics, Mayo Clinic, 200 1 St SW, Rochester, Minnesota USA
| | - Robert A. Rizza
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic, 200 1 St SW, 5-194 Joseph, Rochester, Minnesota USA
| | - Claudio Cobelli
- Department of Information Engineering, Universita’ di Padova, Via Gradenigo 6B, Padova, Italy
| | - Adrian Vella
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic, 200 1 St SW, 5-194 Joseph, Rochester, Minnesota USA
| |
Collapse
|
19
|
Hædersdal S, Lund A, Knop FK, Vilsbøll T. The Role of Glucagon in the Pathophysiology and Treatment of Type 2 Diabetes. Mayo Clin Proc 2018; 93:217-239. [PMID: 29307553 DOI: 10.1016/j.mayocp.2017.12.003] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 12/04/2017] [Accepted: 12/07/2017] [Indexed: 12/19/2022]
Abstract
Type 2 diabetes is a disease involving both inadequate insulin levels and increased glucagon levels. While glucagon and insulin work together to achieve optimal plasma glucose concentrations in healthy individuals, the usual regulatory balance between these 2 critical pancreatic hormones is awry in patients with diabetes. Although clinical discussion often focuses on the role of insulin, glucagon is equally important in understanding type 2 diabetes. Furthermore, an awareness of the role of glucagon is essential to appreciate differences in the mechanisms of action of various classes of glucose-lowering therapies. Newer drug classes such as dipeptidyl peptidase-4 inhibitors and glucagon-like peptide-1 receptor agonists improve glycemic control, in part, by affecting glucagon levels. This review provides an overview of the effect of glucose-lowering therapies on glucagon on the basis of an extensive PubMed literature search to identify clinical studies of glucose-lowering therapies in type 2 diabetes that included assessment of glucagon. Clinical practice currently benefits from available therapies that impact the glucagon regulatory pathway. As clinicians look to the future, improved treatment strategies are likely to emerge that will either use currently available therapies whose mechanisms of action complement each other or take advantage of new therapies based on an improved understanding of glucagon pathophysiology.
Collapse
Affiliation(s)
- Sofie Hædersdal
- Center for Diabetes Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
| | - Asger Lund
- Center for Diabetes Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
| | - Filip K Knop
- Center for Diabetes Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark; Faculty of Health and Medical Sciences, Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Tina Vilsbøll
- Center for Diabetes Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark; Steno Diabetes Center Copenhagen, University of Copenhagen, Gentofte, Denmark; Faculty of Health and Medical Sciences, Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark.
| |
Collapse
|
20
|
Sharma A, Laurenti MC, Dalla Man C, Varghese RT, Cobelli C, Rizza RA, Matveyenko A, Vella A. Glucose metabolism during rotational shift-work in healthcare workers. Diabetologia 2017; 60:1483-1490. [PMID: 28551698 PMCID: PMC5860643 DOI: 10.1007/s00125-017-4317-0] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 04/26/2017] [Indexed: 01/05/2023]
Abstract
AIMS/HYPOTHESIS Shift-work is associated with circadian rhythm disruption and an increased risk of obesity and type 2 diabetes. We sought to determine the effect of rotational shift-work on glucose metabolism in humans. METHODS We studied 12 otherwise healthy nurses performing rotational shift-work using a randomised crossover study design. On each occasion, participants underwent an isotope-labelled mixed meal test during a simulated day shift and a simulated night shift, enabling simultaneous measurement of glucose flux and beta cell function using the oral minimal model. We sought to determine differences in fasting and postprandial glucose metabolism during the day shift vs the night shift. RESULTS Postprandial glycaemic excursion was higher during the night shift (381±33 vs 580±48 mmol/l per 5 h, p<0.01). The time to peak insulin and C-peptide and nadir glucagon suppression in response to meal ingestion was also delayed during the night shift. While insulin action did not differ between study days, the beta cell responsivity to glucose (59±5 vs 44±4 × 10-9 min-1; p<0.001) and disposition index were decreased during the night shift. CONCLUSIONS/INTERPRETATION Impaired beta cell function during the night shift may result from normal circadian variation, the effect of rotational shift-work or a combination of both. As a consequence, higher postprandial glucose concentrations are observed during the night shift.
Collapse
Affiliation(s)
- Anu Sharma
- Endocrine Research Unit, Department of Endocrinology, Diabetes and Nutrition, Mayo Clinic College of Medicine, 200 First St SW, 5-194 Joseph, Rochester, MN, 55905, USA
| | | | - Chiara Dalla Man
- Department of Information Engineering, University of Padua, Padua, Italy
| | - Ron T Varghese
- Endocrine Research Unit, Department of Endocrinology, Diabetes and Nutrition, Mayo Clinic College of Medicine, 200 First St SW, 5-194 Joseph, Rochester, MN, 55905, USA
| | - Claudio Cobelli
- Department of Information Engineering, University of Padua, Padua, Italy
| | - Robert A Rizza
- Endocrine Research Unit, Department of Endocrinology, Diabetes and Nutrition, Mayo Clinic College of Medicine, 200 First St SW, 5-194 Joseph, Rochester, MN, 55905, USA
| | - Aleksey Matveyenko
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - Adrian Vella
- Endocrine Research Unit, Department of Endocrinology, Diabetes and Nutrition, Mayo Clinic College of Medicine, 200 First St SW, 5-194 Joseph, Rochester, MN, 55905, USA.
| |
Collapse
|
21
|
Varghese RT, Dalla Man C, Sharma A, Viegas I, Barosa C, Marques C, Shah M, Miles JM, Rizza RA, Jones JG, Cobelli C, Vella A. Mechanisms Underlying the Pathogenesis of Isolated Impaired Glucose Tolerance in Humans. J Clin Endocrinol Metab 2016; 101:4816-4824. [PMID: 27603902 PMCID: PMC5155694 DOI: 10.1210/jc.2016-1998] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Prediabetes is a heterogeneous disorder classified on the basis of fasting glucose concentrations and 2-hour glucose tolerance. OBJECTIVE We sought to determine the relative contributions of insulin secretion and action to the pathogenesis of isolated impaired glucose tolerance (IGT). DESIGN The study consisted of an oral glucose tolerance test and a euglycemic clamp performed in two cohorts matched for anthropometric characteristics and fasting glucose but discordant for glucose tolerance. SETTING An inpatient clinical research unit at an academic medical center. PATIENTS OR OTHER PARTICIPANTS Twenty-five subjects who had normal fasting glucose (NFG) and normal glucose tolerance (NGT) and 19 NFG/IGT subjects participated in this study. INTERVENTION(S) Subjects underwent a seven-sample oral glucose tolerance test and a 4-hour euglycemic, hyperinsulinemic clamp on separate occasions. Glucose turnover during the clamp was measured using tracers, and endogenous hormone secretion was inhibited by somatostatin. MAIN OUTCOME MEASURES We sought to determine whether hepatic glucose metabolism, specifically the contribution of gluconeogenesis to endogenous glucose production, differed between subjects with NFG/NGT and those with NFG/IGT. RESULTS Endogenous glucose production did not differ between groups before or during the clamp. Insulin-stimulated glucose disappearance was lower in NFG/IGT (24.6 ± 2.2 vs 35.0 ± 3.6 μmol/kg/min; P = .03). The disposition index was decreased in NFG/IGT (681 ± 102 vs 2231 ± 413 × 10-14 dL/kg/min2 per pmol/L; P < .001). CONCLUSIONS We conclude that innate defects in the regulation of glycogenolysis and gluconeogenesis do not contribute to NFG/IGT. However, insulin-stimulated glucose disposal is impaired, exacerbating defects in β-cell function.
Collapse
Affiliation(s)
- Ron T Varghese
- Division of Endocrinology, Diabetes, and Metabolism (R.T.V., A.S., M.S., J.M.M., R.A.R., A.V.), Mayo Clinic College of Medicine, Rochester, Minnesota 55905; Department of Information Engineering (C.D.M., C.C.), Universitá di Padova, 35122 Padova, Italy; Center for Neurosciences and Cell Biology (I.V., C.B., C.M., J.G.J.), University of Coimbra, 3000-370 Coimbra, Portugal; and APDP-Portuguese Diabetes Association (J.G.J.), 1250-203 Lisbon, Portugal
| | - Chiara Dalla Man
- Division of Endocrinology, Diabetes, and Metabolism (R.T.V., A.S., M.S., J.M.M., R.A.R., A.V.), Mayo Clinic College of Medicine, Rochester, Minnesota 55905; Department of Information Engineering (C.D.M., C.C.), Universitá di Padova, 35122 Padova, Italy; Center for Neurosciences and Cell Biology (I.V., C.B., C.M., J.G.J.), University of Coimbra, 3000-370 Coimbra, Portugal; and APDP-Portuguese Diabetes Association (J.G.J.), 1250-203 Lisbon, Portugal
| | - Anu Sharma
- Division of Endocrinology, Diabetes, and Metabolism (R.T.V., A.S., M.S., J.M.M., R.A.R., A.V.), Mayo Clinic College of Medicine, Rochester, Minnesota 55905; Department of Information Engineering (C.D.M., C.C.), Universitá di Padova, 35122 Padova, Italy; Center for Neurosciences and Cell Biology (I.V., C.B., C.M., J.G.J.), University of Coimbra, 3000-370 Coimbra, Portugal; and APDP-Portuguese Diabetes Association (J.G.J.), 1250-203 Lisbon, Portugal
| | - Ivan Viegas
- Division of Endocrinology, Diabetes, and Metabolism (R.T.V., A.S., M.S., J.M.M., R.A.R., A.V.), Mayo Clinic College of Medicine, Rochester, Minnesota 55905; Department of Information Engineering (C.D.M., C.C.), Universitá di Padova, 35122 Padova, Italy; Center for Neurosciences and Cell Biology (I.V., C.B., C.M., J.G.J.), University of Coimbra, 3000-370 Coimbra, Portugal; and APDP-Portuguese Diabetes Association (J.G.J.), 1250-203 Lisbon, Portugal
| | - Cristina Barosa
- Division of Endocrinology, Diabetes, and Metabolism (R.T.V., A.S., M.S., J.M.M., R.A.R., A.V.), Mayo Clinic College of Medicine, Rochester, Minnesota 55905; Department of Information Engineering (C.D.M., C.C.), Universitá di Padova, 35122 Padova, Italy; Center for Neurosciences and Cell Biology (I.V., C.B., C.M., J.G.J.), University of Coimbra, 3000-370 Coimbra, Portugal; and APDP-Portuguese Diabetes Association (J.G.J.), 1250-203 Lisbon, Portugal
| | - Catia Marques
- Division of Endocrinology, Diabetes, and Metabolism (R.T.V., A.S., M.S., J.M.M., R.A.R., A.V.), Mayo Clinic College of Medicine, Rochester, Minnesota 55905; Department of Information Engineering (C.D.M., C.C.), Universitá di Padova, 35122 Padova, Italy; Center for Neurosciences and Cell Biology (I.V., C.B., C.M., J.G.J.), University of Coimbra, 3000-370 Coimbra, Portugal; and APDP-Portuguese Diabetes Association (J.G.J.), 1250-203 Lisbon, Portugal
| | - Meera Shah
- Division of Endocrinology, Diabetes, and Metabolism (R.T.V., A.S., M.S., J.M.M., R.A.R., A.V.), Mayo Clinic College of Medicine, Rochester, Minnesota 55905; Department of Information Engineering (C.D.M., C.C.), Universitá di Padova, 35122 Padova, Italy; Center for Neurosciences and Cell Biology (I.V., C.B., C.M., J.G.J.), University of Coimbra, 3000-370 Coimbra, Portugal; and APDP-Portuguese Diabetes Association (J.G.J.), 1250-203 Lisbon, Portugal
| | - John M Miles
- Division of Endocrinology, Diabetes, and Metabolism (R.T.V., A.S., M.S., J.M.M., R.A.R., A.V.), Mayo Clinic College of Medicine, Rochester, Minnesota 55905; Department of Information Engineering (C.D.M., C.C.), Universitá di Padova, 35122 Padova, Italy; Center for Neurosciences and Cell Biology (I.V., C.B., C.M., J.G.J.), University of Coimbra, 3000-370 Coimbra, Portugal; and APDP-Portuguese Diabetes Association (J.G.J.), 1250-203 Lisbon, Portugal
| | - Robert A Rizza
- Division of Endocrinology, Diabetes, and Metabolism (R.T.V., A.S., M.S., J.M.M., R.A.R., A.V.), Mayo Clinic College of Medicine, Rochester, Minnesota 55905; Department of Information Engineering (C.D.M., C.C.), Universitá di Padova, 35122 Padova, Italy; Center for Neurosciences and Cell Biology (I.V., C.B., C.M., J.G.J.), University of Coimbra, 3000-370 Coimbra, Portugal; and APDP-Portuguese Diabetes Association (J.G.J.), 1250-203 Lisbon, Portugal
| | - John G Jones
- Division of Endocrinology, Diabetes, and Metabolism (R.T.V., A.S., M.S., J.M.M., R.A.R., A.V.), Mayo Clinic College of Medicine, Rochester, Minnesota 55905; Department of Information Engineering (C.D.M., C.C.), Universitá di Padova, 35122 Padova, Italy; Center for Neurosciences and Cell Biology (I.V., C.B., C.M., J.G.J.), University of Coimbra, 3000-370 Coimbra, Portugal; and APDP-Portuguese Diabetes Association (J.G.J.), 1250-203 Lisbon, Portugal
| | - Claudio Cobelli
- Division of Endocrinology, Diabetes, and Metabolism (R.T.V., A.S., M.S., J.M.M., R.A.R., A.V.), Mayo Clinic College of Medicine, Rochester, Minnesota 55905; Department of Information Engineering (C.D.M., C.C.), Universitá di Padova, 35122 Padova, Italy; Center for Neurosciences and Cell Biology (I.V., C.B., C.M., J.G.J.), University of Coimbra, 3000-370 Coimbra, Portugal; and APDP-Portuguese Diabetes Association (J.G.J.), 1250-203 Lisbon, Portugal
| | - Adrian Vella
- Division of Endocrinology, Diabetes, and Metabolism (R.T.V., A.S., M.S., J.M.M., R.A.R., A.V.), Mayo Clinic College of Medicine, Rochester, Minnesota 55905; Department of Information Engineering (C.D.M., C.C.), Universitá di Padova, 35122 Padova, Italy; Center for Neurosciences and Cell Biology (I.V., C.B., C.M., J.G.J.), University of Coimbra, 3000-370 Coimbra, Portugal; and APDP-Portuguese Diabetes Association (J.G.J.), 1250-203 Lisbon, Portugal
| |
Collapse
|
22
|
Ahrén B, Foley JE. Improved glucose regulation in type 2 diabetic patients with DPP-4 inhibitors: focus on alpha and beta cell function and lipid metabolism. Diabetologia 2016; 59:907-17. [PMID: 26894277 DOI: 10.1007/s00125-016-3899-2] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 01/22/2016] [Indexed: 12/19/2022]
Abstract
Inhibition of dipeptidyl peptidase-4 (DPP-4) is an established glucose-lowering strategy for the management of type 2 diabetes mellitus. DPP-4 inhibitors reduce both fasting and postprandial plasma glucose levels, resulting in reduced HbA1c with low risk for hypoglycaemia and weight gain. They act primarily by preventing inactivation of the incretin hormones glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1, thereby prolonging the enhanced endogenous levels of these hormones after meal ingestion. This in turn causes islet and extrapancreatic effects, including increased glucose sensing in islet alpha and beta cells. These effects result in increased insulin secretion and decreased glucagon secretion being more effective in hyperglycaemic states and reduced insulin secretion and increased glucagon secretion being more effective during hypoglycaemia. Other secondary pharmacological actions of DPP-4 inhibitors include mobilisation and burning of fat during meals, decrease in fat extraction from the gut, reduction of fasting lipolysis and liver fat and increase in LDL particle size. These actions contribute to the clinical effects of DPP-4 inhibition, and the reduced demand for insulin could also lead to a durability benefit. This review summarises the current knowledge of the secondary pharmacological actions of DPP-4 inhibitors that lead to improved glucose regulation in patients with type 2 diabetes, focusing on alpha and beta cell function and lipid metabolism.
Collapse
Affiliation(s)
- Bo Ahrén
- Faculty of Medicine, Department of Clinical Sciences Lund, Lund University, B11 BMC, Sölvegatan 19, 22184, Lund, Sweden.
| | - James E Foley
- World Wide Medical Affairs, Novartis Pharmaceuticals Corporation, East Hanover, NJ, USA
| |
Collapse
|
23
|
Rizza RA, Toffolo G, Cobelli C. Accurate Measurement of Postprandial Glucose Turnover: Why Is It Difficult and How Can It Be Done (Relatively) Simply? Diabetes 2016; 65:1133-45. [PMID: 27208180 PMCID: PMC4839208 DOI: 10.2337/db15-1166] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Accepted: 02/25/2016] [Indexed: 12/19/2022]
Abstract
Fasting hyperglycemia occurs when an excessive rate of endogenous glucose production (EGP) is not accompanied by an adequate compensatory increase in the rate of glucose disappearance (Rd). The situation following food ingestion is more complex as the amount of glucose that reaches the circulation for disposal is a function of the systemic rate of appearance of the ingested glucose (referred to as the rate of meal appearance [Rameal]), the pattern and degree of suppression of EGP, and the rapidity of stimulation of the Rd In an effort to measure these processes, Steele et al. proposed what has come to be referred to as the dual-tracer method in which the ingested glucose is labeled with one tracer while a second tracer is infused intravenously at a constant rate. Unfortunately, subsequent studies have shown that although this approach is technically simple, the marked changes in plasma specific activity or the tracer-to-tracee ratio, if stable tracers are used, introduce a substantial error in the calculation of Rameal, EGP, and Rd, thereby leading to incorrect and at times misleading results. This Perspective discusses the causes of these so-called "nonsteady-state" errors and how they can be avoided by the use of the triple-tracer approach.
Collapse
Affiliation(s)
- Robert A Rizza
- Division of Endocrinology, Metabolism, Diabetes, Nutrition, and Internal Medicine, Department of Internal Medicine, Mayo Clinic, Rochester, MN
| | - Gianna Toffolo
- Department of Information Engineering, University of Padova, Padova, Italy
| | - Claudio Cobelli
- Department of Information Engineering, University of Padova, Padova, Italy
| |
Collapse
|
24
|
Wu T, Little TJ, Bound MJ, Borg M, Zhang X, Deacon CF, Horowitz M, Jones KL, Rayner CK. A Protein Preload Enhances the Glucose-Lowering Efficacy of Vildagliptin in Type 2 Diabetes. Diabetes Care 2016; 39:511-7. [PMID: 26786576 DOI: 10.2337/dc15-2298] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 12/24/2015] [Indexed: 02/05/2023]
Abstract
OBJECTIVE Nutrient "preloads" given before meals can attenuate postprandial glycemic excursions, at least partly by slowing gastric emptying and stimulating secretion of the incretins (i.e., glucagon-like peptide-1 [GLP-1] and glucose-dependent insulinotropic polypeptide [GIP]). This study was designed to evaluate whether a protein preload could improve the efficacy of the dipeptidyl peptidase-4 (DPP-4) inhibitor vildagliptin to increase incretin concentrations, slow gastric emptying, and lower postprandial glycemia in type 2 diabetes. RESEARCH DESIGN AND METHODS Twenty-two patients with type 2 diabetes treated with metformin were studied on four occasions, receiving either 50 mg vildagliptin (VILD) or placebo (PLBO) on both the evening before and the morning of each study day. The latter dose was followed after 60 min by a preload drink containing either 25 g whey protein (WHEY) or control flavoring (CTRL), and after another 30 min by a (13)C-octanoate-labeled mashed potato meal. Plasma glucose and hormones, and gastric emptying, were evaluated. RESULTS Compared with PLBO/CTRL, PLBO/WHEY reduced postprandial peak glycemia, increased plasma insulin, glucagon, and incretin hormones (total and intact), and slowed gastric emptying, whereas VILD/CTRL reduced both the peak and area under the curve for glucose, increased plasma intact incretins, and slowed gastric emptying but suppressed plasma glucagon and total incretins (P < 0.05 each). Compared with both PLBO/WHEY and VILD/CTRL, VILD/WHEY was associated with higher plasma intact GLP-1 and GIP, slower gastric emptying, and lower postprandial glycemia (P < 0.05 each). CONCLUSIONS In metformin-treated type 2 diabetes, a protein preload has the capacity to enhance the efficacy of vildagliptin to slow gastric emptying, increase plasma intact incretins, and reduce postprandial glycemia.
Collapse
Affiliation(s)
- Tongzhi Wu
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Tanya J Little
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Michelle J Bound
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Malcolm Borg
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia
| | - Xiang Zhang
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Carolyn F Deacon
- Department of Biomedical Science, University of Copenhagen, Copenhagen, Denmark
| | - Michael Horowitz
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Karen L Jones
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Christopher K Rayner
- Discipline of Medicine, The University of Adelaide, Adelaide, Australia Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| |
Collapse
|
25
|
Dalla Man C, Micheletto F, Sathananthan M, Vella A, Cobelli C. Model-Based Quantification of Glucagon-Like Peptide-1-Induced Potentiation of Insulin Secretion in Response to a Mixed Meal Challenge. Diabetes Technol Ther 2016; 18:39-46. [PMID: 26756104 PMCID: PMC4717506 DOI: 10.1089/dia.2015.0146] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND Glucagon-like peptide-1 (GLP-1) is a powerful insulin secretagogue that is secreted in response to meal ingestion. The ability to quantify the effect of GLP-1 on insulin secretion could provide insights into the pathogenesis and treatment of diabetes. We used a modification of a model of GLP-1 action on insulin secretion using data from a hyperglycemic clamp with concomitant GLP-1 infusion. We tested this model using data from a mixed meal test (MMT), thereby measuring GLP-1-induced potentiation of insulin secretion in response to a meal. MATERIALS AND METHODS The GLP-1 model is based on the oral C-peptide minimal model and assumes that over-basal insulin secretion depends linearly on GLP-1 concentration through the parameter Π, representing the β-cell sensitivity to GLP-1. The model was tested on 62 subjects across the spectrum of glucose tolerance (age, 53 ± 1 years; body mass index, 29.7 ± 0.6 kg/m(2)) studied with an MMT and provided a precise estimate of both β-cell responsivity and Π indices. By combining Π with a measure of L-cell responsivity to glucose, one obtains a potentiation index (PI) (i.e., a measure of the L-cell's function in relation to prevailing β-cell sensitivity to GLP-1). RESULTS Model-based measurement of GLP-1-induced insulin secretion demonstrates that the PI is significantly reduced in people with impaired glucose tolerance, compared with those with normal glucose tolerance. CONCLUSIONS We describe a model that can quantitate the GLP-1-based contribution to insulin secretion in response to meal ingestion. This methodology will allow a better understanding of β-cell function at various stages of glucose tolerance.
Collapse
Affiliation(s)
- Chiara Dalla Man
- Department of Information Engineering, University of Padua, Padua, Italy
| | | | - Matheni Sathananthan
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic College of Medicine, Rochester, Minnesota
| | - Adrian Vella
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic College of Medicine, Rochester, Minnesota
| | - Claudio Cobelli
- Department of Information Engineering, University of Padua, Padua, Italy
| |
Collapse
|
26
|
Sathananthan M, Shah M, Edens KL, Grothe KB, Piccinini F, Farrugia LP, Micheletto F, Man CD, Cobelli C, Rizza RA, Camilleri M, Vella A. Six and 12 Weeks of Caloric Restriction Increases β Cell Function and Lowers Fasting and Postprandial Glucose Concentrations in People with Type 2 Diabetes. J Nutr 2015; 145:2046-51. [PMID: 26246321 PMCID: PMC4548160 DOI: 10.3945/jn.115.210617] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Accepted: 07/10/2015] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Caloric restriction alone has been shown to improve insulin action and fasting glucose metabolism; however, the mechanism by which this occurs remains uncertain. OBJECTIVE We sought to quantify the effect of caloric restriction on β cell function and glucose metabolism in people with type 2 diabetes. METHODS Nine subjects (2 men, 7 women) with type 2 diabetes [BMI (in kg/m(2)): 40.6 ± 1.4; age: 58 ± 3 y; glycated hemoglobin: 6.9% ± 0.2%] were studied using a triple-tracer mixed meal after withdrawal of oral diabetes therapy. The oral minimal model was used to measure β cell function. Caloric restriction limited subjects to a pureed diet (<900 kcal/d) for the 12 wk of study. The studies were repeated after 6 and 12 wk of caloric restriction. RESULTS Fasting glucose concentrations decreased significantly from baseline after 6 wk of caloric restriction with no further reduction after a further 6 wk of caloric restriction (9.8 ± 1.3, 5.9 ± 0.2, and 6.2 ± 0.3 mmol/L at baseline and after 6 and 12 wk of caloric restriction, respectively; P = 0.01) because of decreased fasting endogenous glucose production (EGP: 20.4 ± 1.1, 16.2 ± 0.8, and 17.4 ± 1.1 μmol · kg(-1) · min(-1) at baseline and after 6 and 12 wk of caloric restriction, respectively; P = 0.03). These changes were accompanied by an improvement in β cell function measured by the disposition index (189 ± 51, 436 ± 68, and 449 ± 67 10(-14) dL · kg(-1) · min(-2) · pmol(-1) at baseline and after 6 and 12 wk of caloric restriction, respectively; P = 0.01). CONCLUSIONS Six weeks of caloric restriction lowers fasting glucose and EGP with accompanying improvements in β cell function in people with type 2 diabetes. An additional 6 wk of caloric restriction maintained the improvement in glucose metabolism. This trial was registered at clinicaltrials.gov as NCT01094054.
Collapse
Affiliation(s)
| | - Meera Shah
- Divisions of Endocrinology, Diabetes & Metabolism and
| | - Kim L Edens
- Divisions of Endocrinology, Diabetes & Metabolism and
| | - Karen B Grothe
- Department of Psychiatry & Psychology, Mayo Clinic College of Medicine, Rochester, MN; and
| | | | | | | | - Chiara Dalla Man
- Department of Information Engineering, University of Padua, Padua, Italy
| | - Claudio Cobelli
- Department of Information Engineering, University of Padua, Padua, Italy
| | | | | | - Adrian Vella
- Divisions of Endocrinology, Diabetes & Metabolism and
| |
Collapse
|
27
|
Pacini G, Mari A, Fouqueray P, Bolze S, Roden M. Imeglimin increases glucose-dependent insulin secretion and improves β-cell function in patients with type 2 diabetes. Diabetes Obes Metab 2015; 17:541-545. [PMID: 25694060 DOI: 10.1111/dom.12452] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Revised: 02/03/2015] [Accepted: 02/16/2015] [Indexed: 12/13/2022]
Abstract
AIMS To assess the glucose-stimulated insulin secretion effect of imeglimin in patients with type 2 diabetes. METHODS We conducted a double-blind, randomized, placebo-controlled study in 33 patients with type 2 diabetes [glycated haemoglobin 6.8 ± 0.1% (51 mmol/mol)], who were drug-naïve or withdrawn from their previous metformin monotherapy for 2 weeks and received imeglimin 1500 mg twice daily or placebo for 1 week. Glucose-stimulated insulin secretion was assessed using a hyperglycaemic clamp. The primary endpoint was insulin secretion as defined by total insulin response [incremental area under the curve (iAUC)0-45 min ] and insulin secretion rate (ISR) calculated from C-peptide deconvolution. β-cell glucose sensitivity at steady state (second phase: 25-45 min), hepatic insulin extraction and insulin clearance were also calculated. RESULTS Imeglimin treatment for 7 days raised the insulin secretory response to glucose by +112% (iAUC0-45 , p = 0.035), first-phase ISR by +110% (p = 0.034) and second-phase ISR by +29% (p = 0.031). Imeglimin improved β-cell glucose sensitivity by +36% (p = 0.034) and tended to decrease hepatic insulin extraction (-13%; p = 0.056). Imeglimin did not affect glucagon secretion. CONCLUSIONS In patients with type 2 diabetes, imeglimin improves β-cell function, which may contribute to the glucose-lowering effect observed with imeglimin in clinical trials.
Collapse
Affiliation(s)
- G Pacini
- Metabolic (Modeling) Unit, Institute of Biomedical Engineering, Padova, Italy
| | - A Mari
- Metabolic (Modeling) Unit, Institute of Biomedical Engineering, Padova, Italy
| | | | | | - M Roden
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Düsseldorf, Germany
- Department of Endocrinology and Diabetology, Medical Faculty, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
- German Center for Diabetes Research, Düsseldorf, Germany
| |
Collapse
|
28
|
Baek JH, Jin SM, Kaku K, Jung JA, Kim JR, Ko JW, Kim MJ, Lee SY, Huh WS, Kim JH. Efficacy of mitiglinide and sitagliptin, alone or in combination, on postprandial excursion and glycemic variability assessed by continuous glucose monitoring: a post hoc analysis with single-day treatment. Expert Opin Pharmacother 2015; 16:1127-36. [PMID: 25881690 DOI: 10.1517/14656566.2015.1035646] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
OBJECTIVE To compare the efficacy of mitiglinide and sitagliptin, alone or in combination, on postprandial excursion and glycemic variability assessed by continuous glucose monitoring (CGM) in a single-day treatment setting. METHODS This was a post hoc analysis of a randomized crossover study comparing the efficacy of sitagliptin, mitiglinide and the combination of these two drugs. Twenty-four hour CGM was performed before and after a single-day treatment with each drug alone or in combination. RESULTS Mean glucose levels were decreased in all groups. The average of three postprandial glucose excursions AUC (average of all three 4-h postprandial periods throughout the day) (AUCpp-average) decreased in the mitiglinide and combination treatment groups, but not in the sitagliptin group. The lowering effect on AUCpp-average was greater in patients given mitiglinide (-47 mg/dl, p < 0.001) or combination treatment (-66 mg/dl, p < 0.001) compared with sitagliptin alone (-18 mg/dl). The reduction in mean amplitude of glycemic excursion was greater with mitiglinide (-29.3 mg/dl, p < 0.001) and combination treatment (-28.3 mg/dl, p < 0.01) than with sitagliptin alone (-8.9 mg/dl). CONCLUSIONS Mitiglinide or combination treatment resulted in lower glycemic variability and postprandial glucose excursion than sitagliptin alone; however, the results of this single-day pharmacodynamics study cannot be generalized to a clinical setting.
Collapse
Affiliation(s)
- Jong-Ha Baek
- Sungkyunkwan University School of Medicine, Samsung Medical Center, Department of Medicine , Seoul , South Korea +82 2 3410 1580 ; +82 2 3410 3849 ; ;
| | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Javed A, Vella A, Balagopal PB, Fischer PR, Weaver AL, Piccinini F, Dalla Man C, Cobelli C, Giesler PD, Laugen JM, Kumar S. Cholecalciferol supplementation does not influence β-cell function and insulin action in obese adolescents: a prospective double-blind randomized trial. J Nutr 2015; 145:284-90. [PMID: 25644349 PMCID: PMC6619681 DOI: 10.3945/jn.114.202010] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND There is increasing interest in the extraskeletal effects of vitamin D, particularly in the obese state with regard to the development of insulin resistance and diabetes. OBJECTIVE The objective of the study was to determine the effect of 2 doses of cholecalciferol (vitamin D3) supplementation on insulin action (Si) and pancreatic β-cell function in obese adolescents. METHODS We performed a 12-wk double-blind, randomized comparison of the effect of vitamin D3 supplementation on Si and β-cell function in obese Caucasian adolescents (body mass index > 95(th) percentile). The subjects were randomly assigned to receive either 400 IU/d (n = 25) or 2000 IU/d (n = 26) of vitamin D3. Each subject underwent a 7-sample 75 g oral glucose tolerance test, with glucose, insulin, and C-peptide measurements, to calculate Si and β-cell function as assessed by the disposition index (DI), with use of the oral minimal model before and after supplementation. A total of 51 subjects aged 15.0 ± 1.9 y were enrolled. Included for analysis at follow-up were a total of 46 subjects (20 male and 26 female adolescents), 23 in each group. RESULTS Initial serum 25-hydroxyvitamin D [25(OH)D] was 24.0 ± 8.1 μg/L. There was no correlation between 25(OH)D concentrations and Si or DI. There was a modest but significant increase in 25(OH)D concentration in the 2000 IU/d group (3.1 ± 6.5 μg/L, P = 0.04) but not in the 400 IU/d group (P = 0.39). There was no change in Si or DI following vitamin D3 supplementation in either of the treatment groups (all P > 0.10). CONCLUSIONS The current study shows no effect from vitamin D3 supplementation, irrespective of its dose, on β-cell function or insulin action in obese nondiabetic adolescents with relatively good vitamin D status. Whether obese adolescents with vitamin D deficiency and impaired glucose metabolism would respond differently to vitamin D3 supplementation remains unclear and warrants further studies. This trial was registered at clinicaltrials.gov as NCT00858247.
Collapse
Affiliation(s)
- Asma Javed
- Division of Pediatric Endocrinology, Department of Pediatric and Adolescent
Medicine, Mayo Clinic, Rochester, MN
| | - Adrian Vella
- Division of Endocrinology and Metabolism, Mayo Clinic, Rochester, MN
| | | | - Philip R Fischer
- Division of General Pediatric and Adolescent Medicine, Department of
Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN
| | - Amy L Weaver
- Division of Biomedical Statistics and Informatics, Department of Health
Sciences Research, Mayo Clinic, Rochester, MN
| | | | - Chiara Dalla Man
- Department of Electronics and Informatics, University of Padua, Padua,
Italy
| | - Claudio Cobelli
- Department of Electronics and Informatics, University of Padua, Padua,
Italy
| | - Paula D Giesler
- Endocrine Research Unit, Division of Endocrinology, Diabetes, Metabolism,
and Nutrition, Department of Internal Medicine, Mayo Clinic, Rochester, MN
| | - Jeanette M Laugen
- Endocrine Research Unit, Division of Endocrinology, Diabetes, Metabolism,
and Nutrition, Department of Internal Medicine, Mayo Clinic, Rochester, MN
| | | |
Collapse
|
30
|
Shinjo T, Nakatsu Y, Iwashita M, Sano T, Sakoda H, Ishihara H, Kushiyama A, Fujishiro M, Nishimura F, Asano T. High-fat diet feeding significantly attenuates anagliptin-induced regeneration of islets of Langerhans in streptozotocin-induced diabetic mice. Diabetol Metab Syndr 2015; 7:50. [PMID: 26097511 PMCID: PMC4475295 DOI: 10.1186/s13098-015-0047-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 05/27/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND DPP-4 inhibitors reportedly exert effects on both alpha and beta cells, and promote the proliferation and survival of beta cells. We investigated the effects of anagliptin on structurally-impaired islets of Langerhans in streptozotocin (STZ)-treated mice, fed either a normal or a high-fat diet. Pdx-1 expression in the pancreas and serum insulin/glucagon concentrations were also examined. FINDINGS Anagliptin treatment significantly up-regulated pancreatic Pdx-1 expression, with elevated serum glucagon-like peptide-1 concentrations, regardless of whether the diet was normal or high-fat. However, interestingly, the beta cell regeneration, structural normalization of islets of Langerhans including alpha cell: beta cell area ratios, and serum insulin elevation, all observed with anagliptin administration in the animals fed a normal diet, were markedly suppressed in the high-fat fed group. CONCLUSIONS High-fat diet feeding clearly weakened the regenerative effects of anagliptin on the islets of Langerhans in STZ-treated mice. Our findings suggest the importance of normalizing lipid metabolism for full manifestation of DPP-4 inhibitor effects on the islets of Langerhans.
Collapse
Affiliation(s)
- Takanori Shinjo
- />Section of Periodontology, Kyushu University Faculty of Dental Science, 3-1-1 Maidashi, Fukuoka, Higashi-ku Japan
| | - Yusuke Nakatsu
- />Division of Molecular Medical Science, Department of Medical Chemistry, Graduate School of Biomedical Sciences, Hiroshima University, 1-2-3 Kasumi, Hiroshima, Minami-ku 734-8551 Japan
| | - Misaki Iwashita
- />Section of Periodontology, Kyushu University Faculty of Dental Science, 3-1-1 Maidashi, Fukuoka, Higashi-ku Japan
| | - Tomomi Sano
- />Division of Cervico-Gnathostomatology, Department of Dental Science for Health Promotion, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan
| | - Hideyuki Sakoda
- />Department of Internal Medicine, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Tokyo, Bunkyo-ku Japan
| | - Hisamitsu Ishihara
- />Division of Diabetes and Metabolic Diseases, Nihon University School of Medicine, 30-1 Oyaguchikami-machi, Tokyo, Itabashi-ku Japan
| | - Akifumi Kushiyama
- />Division of Diabetes and Metabolism, Institute for Adult Disease, Asahi Life Foundation, 1-6-1 Marunouchi, Tokyo, Chiyoda-ku Japan
| | - Midori Fujishiro
- />Department of Internal Medicine, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Tokyo, Bunkyo-ku Japan
| | - Fusanori Nishimura
- />Section of Periodontology, Kyushu University Faculty of Dental Science, 3-1-1 Maidashi, Fukuoka, Higashi-ku Japan
| | - Tomoichiro Asano
- />Division of Molecular Medical Science, Department of Medical Chemistry, Graduate School of Biomedical Sciences, Hiroshima University, 1-2-3 Kasumi, Hiroshima, Minami-ku 734-8551 Japan
| |
Collapse
|
31
|
Abstract
The simultaneous assessment of insulin action, secretion, and hepatic extraction is key to understanding postprandial glucose metabolism in nondiabetic and diabetic humans. We review the oral minimal method (i.e., models that allow the estimation of insulin sensitivity, β-cell responsivity, and hepatic insulin extraction from a mixed-meal or an oral glucose tolerance test). Both of these oral tests are more physiologic and simpler to administer than those based on an intravenous test (e.g., a glucose clamp or an intravenous glucose tolerance test). The focus of this review is on indices provided by physiological-based models and their validation against the glucose clamp technique. We discuss first the oral minimal model method rationale, data, and protocols. Then we present the three minimal models and the indices they provide. The disposition index paradigm, a widely used β-cell function metric, is revisited in the context of individual versus population modeling. Adding a glucose tracer to the oral dose significantly enhances the assessment of insulin action by segregating insulin sensitivity into its glucose disposal and hepatic components. The oral minimal model method, by quantitatively portraying the complex relationships between the major players of glucose metabolism, is able to provide novel insights regarding the regulation of postprandial metabolism.
Collapse
Affiliation(s)
- Claudio Cobelli
- Department of Information Engineering, University of Padova, Padova, Italy
- Corresponding author: Claudio Cobelli,
| | - Chiara Dalla Man
- Department of Information Engineering, University of Padova, Padova, Italy
| | - Gianna Toffolo
- Department of Information Engineering, University of Padova, Padova, Italy
| | - Rita Basu
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Department of Internal Medicine, Mayo Clinic and Foundation, Rochester, MN
| | - Adrian Vella
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Department of Internal Medicine, Mayo Clinic and Foundation, Rochester, MN
| | - Robert Rizza
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Department of Internal Medicine, Mayo Clinic and Foundation, Rochester, MN
| |
Collapse
|
32
|
|
33
|
Shah M, Law JH, Micheletto F, Sathananthan M, Dalla Man C, Cobelli C, Rizza RA, Camilleri M, Zinsmeister AR, Vella A. Contribution of endogenous glucagon-like peptide 1 to glucose metabolism after Roux-en-Y gastric bypass. Diabetes 2014; 63:483-93. [PMID: 24089513 PMCID: PMC3968439 DOI: 10.2337/db13-0954] [Citation(s) in RCA: 112] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The contribution of elevated glucagon-like peptide 1 (GLP-1) to postprandial glucose metabolism after Roux-en-Y gastric bypass (RYGB) has been the subject of uncertainty. We used exendin-9,39, a competitive antagonist of GLP-1, to examine glucose metabolism, islet hormone secretion, and gastrointestinal transit in subjects after RYGB and in matched control subjects. Subjects were studied in the presence or absence of exendin-9,39 infused at 300 pmol/kg/min. Exendin-9,39 resulted in an increase in integrated postprandial glucose concentrations post-RYGB (3.6 ± 0.5 vs. 2.0 ± 0.4 mol/6 h, P = 0.001). Exendin-9,39 decreased insulin concentrations (12.3 ± 2.2 vs. 18.1 ± 3.1 nmol/6 h, P = 0.002) and the β-cell response to glucose (Total, 13 ± 1 vs. 11 ± 1 × 10(-9) min(-1), P = 0.01) but did not alter the disposition index (DI). In control subjects, exendin-9,39 also increased glucose (2.2 ± 0.4 vs. 1.7 ± 0.3 mol/6 h, P = 0.03) without accompanying changes in insulin concentrations, resulting in an impaired DI. Post-RYGB, acceleration of stomach emptying during the first 30 min by exendin-9,39 did not alter meal appearance, and similarly, suppression of glucose production and stimulation of glucose disappearance were unaltered in RYGB subjects. These data indicate that endogenous GLP-1 has effects on glucose metabolism and on gastrointestinal motility years after RYGB. However, it remains uncertain whether this explains all of the changes after RYGB.
Collapse
Affiliation(s)
- Meera Shah
- Division of Endocrinology, Diabetes and Metabolism, Mayo Clinic College of Medicine, Rochester, MN
| | - Jennie H. Law
- Division of Endocrinology, Diabetes and Metabolism, Mayo Clinic College of Medicine, Rochester, MN
| | | | - Matheni Sathananthan
- Division of Endocrinology, Diabetes and Metabolism, Mayo Clinic College of Medicine, Rochester, MN
| | - Chiara Dalla Man
- Department of Information Engineering, University of Padua, Padua, Italy
| | - Claudio Cobelli
- Department of Information Engineering, University of Padua, Padua, Italy
| | - Robert A. Rizza
- Division of Endocrinology, Diabetes and Metabolism, Mayo Clinic College of Medicine, Rochester, MN
| | - Michael Camilleri
- Division of Gastroenterology and Hepatology, Mayo Clinic College of Medicine, Rochester, MN
| | | | - Adrian Vella
- Division of Endocrinology, Diabetes and Metabolism, Mayo Clinic College of Medicine, Rochester, MN
- Corresponding author: Adrian Vella,
| |
Collapse
|
34
|
Sathananthan M, Ikramuddin S, Swain JM, Shah M, Piccinini F, Dalla Man C, Cobelli C, Rizza RA, Camilleri M, Vella A. The effect of vagal nerve blockade using electrical impulses on glucose metabolism in nondiabetic subjects. Diabetes Metab Syndr Obes 2014; 7:305-12. [PMID: 25050073 PMCID: PMC4103924 DOI: 10.2147/dmso.s65733] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
PURPOSE Vagal interruption causes weight loss in humans and decreases endogenous glucose production in animals. However, it is unknown if this is due to a direct effect on glucose metabolism. We sought to determine if vagal blockade using electrical impulses alters glucose metabolism in humans. PATIENTS AND METHODS We utilized a randomized, cross-over study design where participants were studied after 2 weeks of activation or inactivation of vagal nerve blockade (VNB). Seven obese subjects with impaired fasting glucose previously enrolled in a long-term study to examine the effect of VNB on weight took part. We used a standardized triple-tracer mixed meal to enable measurement of the rate of meal appearance, endogenous glucose production, and glucose disappearance. The 550 kcal meal was also labeled with (111)In-diethylene triamine pentaacetic acid (DTPA) to measure gastrointestinal transit. Insulin action and β-cell responsivity indices were estimated using the minimal model. RESULTS Integrated glucose, insulin, and glucagon concentrations did not differ between study days. This was also reflected in a lack of effect on β-cell responsivity and insulin action. Furthermore, fasting and postprandial endogenous glucose production, integrated meal appearance, and glucose disposal did not differ in the presence or absence of VNB. Similarly, gastric emptying and colonic transit were unchanged by VNB. CONCLUSION In this pilot study in nondiabetic humans, electrical vagal blockade had no acute effects on glucose metabolism, insulin secretion and action, or gastric emptying. It remains to be determined if more pronounced effects would be observed in diabetic subjects.
Collapse
Affiliation(s)
- Matheni Sathananthan
- Division of Endocrinology, Diabetes and Metabolism, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Sayeed Ikramuddin
- Division of General Surgery, University of Minnesota, Minneapolis, MN, USA
| | - James M Swain
- Division of General Surgery, Mayo Clinic College of Medicine, Rochester, MN, USA
- Scottsdale Healthcare Bariatric Center, Scottsdale, AZ, USA
| | - Meera Shah
- Division of Endocrinology, Diabetes and Metabolism, Mayo Clinic College of Medicine, Rochester, MN, USA
| | | | - Chiara Dalla Man
- Department of Information Engineering, University of Padua, Padua, Italy
| | - Claudio Cobelli
- Department of Information Engineering, University of Padua, Padua, Italy
| | - Robert A Rizza
- Division of Endocrinology, Diabetes and Metabolism, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Michael Camilleri
- Division of Gastroenterology and Hepatology, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Adrian Vella
- Division of Endocrinology, Diabetes and Metabolism, Mayo Clinic College of Medicine, Rochester, MN, USA
- Correspondence: Adrian Vella, Endocrine Research Unit, Mayo Clinic College of Medicine, 200 First St SW, 5-194 Joseph Rochester, MN 55905, USA, Tel +1 507 255 6515, Fax +1 507 255 4828, Email
| |
Collapse
|
35
|
Smushkin G, Sathananthan M, Piccinini F, Dalla Man C, Law JH, Cobelli C, Zinsmeister AR, Rizza RA, Vella A. The effect of a bile acid sequestrant on glucose metabolism in subjects with type 2 diabetes. Diabetes 2013; 62:1094-101. [PMID: 23250357 PMCID: PMC3609563 DOI: 10.2337/db12-0923] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We designed an experiment to examine the effect of bile acid sequestration with Colesevelam on fasting and postprandial glucose metabolism in type 2 diabetes. To do so, we tested the hypothesis that Colesevelam increases the disposition index (DI), and this increase is associated with increased glucagon-like peptide-1 (GLP-1) concentrations. Thirty-eight subjects on metformin monotherapy were studied using a double-blind, placebo-controlled, parallel-group design. Subjects were studied before and after 12 weeks of Colesevelam or placebo using a labeled triple-tracer mixed meal to measure the rate of meal appearance (Meal Ra), endogenous glucose production (EGP), and glucose disappearance (Rd). Insulin sensitivity and β-cell responsivity indices were estimated using the oral minimal model and then used to calculate DI. Therapy with Colesevelam was associated with a decrease in fasting (7.0 ± 0.2 vs. 6.6 ± 0.2 mmol/L; P = 0.004) and postprandial glucose concentrations (3,145 ± 138 vs. 2,896 ± 127 mmol/6 h; P = 0.01) in the absence of a change in insulin concentrations. Minimal model-derived indices of insulin secretion and action were unchanged. Postprandial GLP-1 concentrations were not altered by Colesevelam. Although EGP and Rd were unchanged, integrated Meal Ra was decreased by Colesevelam (5,191 ± 204 vs. 5,817 ± 204 μmol/kg/6 h; P = 0.04), suggesting increased splanchnic sequestration of meal-derived glucose.
Collapse
Affiliation(s)
- Galina Smushkin
- Division of Endocrinology, Diabetes and Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota
| | - Matheni Sathananthan
- Division of Endocrinology, Diabetes and Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota
| | | | - Chiara Dalla Man
- Department of Information Engineering, University of Padua, Padua, Italy
| | - Jennie H. Law
- Division of Endocrinology, Diabetes and Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota
| | - Claudio Cobelli
- Department of Information Engineering, University of Padua, Padua, Italy
| | - Alan R. Zinsmeister
- Division of Biostatistics, Mayo Clinic College of Medicine, Rochester, Minnesota
| | - Robert A. Rizza
- Division of Endocrinology, Diabetes and Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota
| | - Adrian Vella
- Division of Endocrinology, Diabetes and Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota
- Corresponding author: Adrian Vella,
| |
Collapse
|
36
|
|
37
|
Muscelli E, Casolaro A, Gastaldelli A, Mari A, Seghieri G, Astiarraga B, Chen Y, Alba M, Holst J, Ferrannini E. Mechanisms for the antihyperglycemic effect of sitagliptin in patients with type 2 diabetes. J Clin Endocrinol Metab 2012; 97:2818-26. [PMID: 22685234 DOI: 10.1210/jc.2012-1205] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Dipeptidyl peptidase IV (DPP-4) inhibitors improve glycemic control in patients with type 2 diabetes. The underlying mechanisms (incretin effect, β-cell function, endogenous glucose production) are not well known. OBJECTIVE The aim of the study was to examine mechanisms of the antihyperglycemic effect of DPP-4 inhibitors. DESIGN, SETTING, AND PATIENTS We administered a mixed meal with glucose tracers ([6,6-(2)H(2)]-glucose infused, [1-(2)H]-glucose ingested), and on a separate day, a glucose infusion matched the glucose responses to the meal (isoglycemic test) in 50 type 2 diabetes patients (hemoglobin A(1c) = 7.4 ± 0.8%) and seven controls; 47 diabetic completers were restudied after 6 wk. Glucose fluxes were calculated, and β-cell function was assessed by mathematical modeling. The incretin effect was calculated as the ratio of oral to iv insulin secretion. INTERVENTION We conducted a 6-wk, double-blind, randomized treatment with sitagliptin (100 mg/d; n = 25) or placebo (n = 22). RESULTS Relative to placebo, meal-induced changes in fasting glucose and glucose area under the curve (AUC) were greater with sitagliptin, in parallel with a lower appearance of oral glucose [difference (post-pre) AUC = -353 ± 915 vs. +146 ± 601 μmol · kg(-1) · 5 h] and greater suppression of endogenous glucose production. Insulin sensitivity improved 10%, whereas total insulin secretion was unchanged. During the meal, β-cell glucose sensitivity improved (+19[29] vs. 5[21] pmol · min(-1) · m(-2) · mm(-1); median [interquartile range]) and glucagon AUC decreased (19.6 ± 7.5 to 17.3 ± 7.1 ng · ml(-1) · 5 h), whereas intact glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 AUC increased with sitagliptin vs. placebo. The incretin effect was unchanged because sitagliptin increased β-cell glucose sensitivity also during the isoglycemic test. CONCLUSIONS Chronic sitagliptin treatment improves glycemic control by lowering the appearance of oral glucose, postprandial endogenous glucose release, and glucagon response, and by improving insulin sensitivity and β-cell glucose sensing in response to both oral and iv glucose.
Collapse
Affiliation(s)
- Elza Muscelli
- Department of Internal Medicine, University of Pisa School of Medicine, 56100 Pisa, Italy
| | | | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Suntsov YI. Modern antihyperglycemic agents prescribed in Russia for type 2 diabetes mellitus. DIABETES MELLITUS 2012. [DOI: 10.14341/2072-0351-5971] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Aims. To conduct an analysis of modern antihyperglycemic prescription patterns in type 2 diabetes mellitus (T2DM). Materials and methods. Russian DM State registry was studied. Results. We obtained absolute and comparative data on use of insulin analogues, dipeptidyl peptidase-4 (DPP-4) inhibitors and glucagon-like peptide-1 agonists in treatment of T2DM. Conclusion. Percentage of DPP-4 inhibitors and GLP-1 analogues in T2DM treatment patterns remains nominal and does not exceed0.2%, which is significantly lower than in the majority of other countries. Insulin analogues are prescribed considerably more frequentlyand currently appear to be the most promising agents for treatment of T2DM.
Collapse
|
39
|
van Genugten RE, van Raalte DH, Diamant M. Dipeptidyl peptidase-4 inhibitors and preservation of pancreatic islet-cell function: a critical appraisal of the evidence. Diabetes Obes Metab 2012; 14:101-11. [PMID: 21752172 DOI: 10.1111/j.1463-1326.2011.01473.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Type 2 diabetes mellitus (T2DM) develops as a consequence of progressive β-cell dysfunction in the presence of insulin resistance. None of the currently-available T2DM therapies is able to change the course of the disease by halting the relentless decline in pancreatic islet cell function. Recently, dipeptidyl peptidase (DPP)-4 inhibitors, or incretin enhancers, have been introduced in the treatment of T2DM. This class of glucose-lowering agents enhances endogenous glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) levels by blocking the incretin-degrading enzyme DPP-4. DPP-4 inhibitors may restore the deranged islet-cell balance in T2DM, by stimulating meal-related insulin secretion and by decreasing postprandial glucagon levels. Moreover, in rodent studies, DPP-4 inhibitors demonstrated beneficial effects on (functional) β-cell mass and pancreatic insulin content. Studies in humans with T2DM have indicated improvement of islet-cell function, both in the fasted state and under postprandial conditions and these beneficial effects were sustained in studies with a duration up to 2 years. However, there is at present no evidence in humans to suggest that DPP-4 inhibitors have durable effects on β-cell function after cessation of therapy. Long-term, large-sized trials using an active blood glucose lowering comparator followed by a sufficiently long washout period after discontinuation of the study drug are needed to assess whether DPP-4 inhibitors may durably preserve pancreatic islet-cell function in patients with T2DM.
Collapse
Affiliation(s)
- R E van Genugten
- Diabetes Center, Department of Internal Medicine, VU University Medical Center, Amsterdam, The Netherlands.
| | | | | |
Collapse
|
40
|
Smushkin G, Sathananthan A, Man CD, Zinsmeister AR, Camilleri M, Cobelli C, Rizza RA, Vella A. Defects in GLP-1 response to an oral challenge do not play a significant role in the pathogenesis of prediabetes. J Clin Endocrinol Metab 2012; 97:589-98. [PMID: 22090278 PMCID: PMC3275363 DOI: 10.1210/jc.2011-2561] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
CONTEXT There has been much speculation as to whether defects in glucagon-like peptide-1 (GLP-1) secretion play a role in the pathogenesis of type 2 diabetes and the progression from normal glucose tolerance to prediabetes and diabetes. OBJECTIVE Our objective was to determine whether fasting and postchallenge concentrations of active and total GLP-1 decrease as glucose tolerance and insulin secretion worsen across the spectrum of prediabetes. DESIGN This was a cross-sectional study. SETTING The study was performed in the clinical research unit of an academic medical center. PARTICIPANTS Participants included 165 subjects with a fasting glucose below 7.0 mmol/liter and not taking medications known to affect gastrointestinal motility or glucose metabolism. INTERVENTION Intervention included a 2-h, 75-g oral glucose tolerance test with insulin, C-peptide, glucagon, and GLP-1 measurements at seven time points. MAIN OUTCOME MEASURE We evaluated the association of integrated, incremental active, and total GLP-1 concentrations with integrated, incremental glucose response to 75 g oral glucose. RESULTS After accounting for covariates, there was no evidence of a relationship of incremental glucose concentrations after oral glucose tolerance test with active and total GLP-1 (r(s) = -0.16 and P = 0.14, and r(s) = 0.00 and P > 0.9, respectively). There also was no association of GLP-1 concentrations with insulin secretion and action. CONCLUSIONS The lack of association of GLP-1 concentrations with glucose tolerance status and with insulin secretion and action in a cohort encompassing the full spectrum of prediabetes strongly argues against a significant contribution of defects in GLP-1 secretion to the pathogenesis of prediabetes.
Collapse
Affiliation(s)
- Galina Smushkin
- Division of Endocrinology, Mayo Clinic, Rochester, Minnesota 55905, USA
| | | | | | | | | | | | | | | |
Collapse
|
41
|
Affiliation(s)
- Ananda Basu
- Endocrine Research Unit, Division of Endocrinology and Metabolism, Mayo College of Medicine, Rochester, Minnesota, USA.
| | | | | |
Collapse
|
42
|
Henry RR, Smith SR, Schwartz SL, Mudaliar SR, Deacon CF, Holst JJ, Duan RY, Chen RS, List JF. Effects of saxagliptin on β-cell stimulation and insulin secretion in patients with type 2 diabetes. Diabetes Obes Metab 2011; 13:850-8. [PMID: 21554520 DOI: 10.1111/j.1463-1326.2011.01417.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIM To study the effect of dipeptidyl peptidase-4 (DPP-4) inhibition with saxagliptin on β-cell function as reflected by the stimulated insulin secretion rate after an enteral glucose load in patients with type 2 diabetes. METHODS Patients in this randomized, parallel-group, double-blind, placebo-controlled study were drug-naïve, aged 43-69 years, with baseline haemoglobin A1c (HbA1c) 5.9-8.1%. Twenty patients received saxagliptin 5 mg once daily; 16 received placebo. Patients were assessed at baseline and week 12 by intravenous hyperglycaemic clamp (0-180 min, fasting state), and intravenous-oral hyperglycaemic clamp (180-480 min, postprandial state) following oral ingestion of 75 g glucose. Primary and secondary endpoints were percent changes from baseline in insulin secretion during postprandial and fasting states, respectively. Insulin secretion was calculated by C-peptide deconvolution. RESULTS After 12 weeks, saxagliptin significantly increased insulin secretion percent change from baseline during the postprandial state by an 18.5% adjusted difference versus placebo (p = 0.04), an improvement associated with increased peak plasma concentrations of intact glucagon-like peptide-1 and glucose-dependent insulinotropic polypeptide. In the fasting state, saxagliptin significantly increased insulin secretion by a 27.9% adjusted difference versus placebo (p = 0.02). Saxagliptin also improved glucagon area under the curve in the postprandial state (adjusted difference -21.8% vs. placebo, p = 0.03). CONCLUSIONS DPP-4 inhibition with saxagliptin improves pancreatic β-cell function in postprandial and fasting states, and decreases postprandial glucagon concentration. Given the magnitude of enhancement of the insulin response in the fasting state, further study into the effect of DPP-4 inhibition on the β-cell is warranted.
Collapse
Affiliation(s)
- R R Henry
- VA San Diego Healthcare System Research Service and University of California San Diego School of Medicine, San Diego, CA, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
43
|
Abstract
Vildagliptin (Galvus®, Jalra®, Xiliarx®) is an orally administered dipeptidyl peptidase-4 (DPP-4) inhibitor. In patients with type 2 diabetes mellitus, vildagliptin 50 mg twice daily is indicated for use in combination with metformin or a thiazolidinedione, and vildagliptin 50 mg once daily is indicated for use in combination with a sulfonylurea. A fixed-dose combination of vildagliptin/metformin (Eucreas®, Icandra®, Zomarist®) is also available. This article reviews the clinical efficacy and tolerability of vildagliptin in patients with type 2 diabetes, as well as summarizing its pharmacological properties. The efficacy of monotherapy or combination therapy with oral vildagliptin in patients with type 2 diabetes has been examined in randomized, double-blind, multicentre trials. Monotherapy with vildagliptin 50 mg once or twice daily reduced glycosylated haemoglobin (HbA(1c)) from baseline to a significantly greater extent than placebo, according to the results of 12- to 52-week trials in patients with type 2 diabetes. In terms of the reduction from baseline in HbA(1c) seen in active comparator trials of 12-104 weeks' duration, the noninferiority of vildagliptin 50 mg twice daily was established versus acarbose or rosiglitazone, the noninferiority of vildagliptin 100 mg once daily (an off-label dosage) versus metformin was established in elderly patients and vildagliptin 50 mg twice daily was more effective than voglibose; however, the noninferiority of vildagliptin 50 mg twice daily versus metformin or gliclazide was not established in two other trials. Combination therapy with vildagliptin 50 mg twice daily plus metformin improved HbA(1c) to a significantly greater extent than monotherapy with metformin and/or vildagliptin alone in patients with type 2 diabetes whose disease was inadequately controlled by metformin monotherapy or who were treatment naive, according to the results of 12- or 24-week trials. In addition, vildagliptin 50 mg twice daily plus metformin demonstrated noninferiority to pioglitazone plus metformin, glimepiride plus metformin or gliclazide plus metformin in terms of the change from baseline in HbA(1c) after 24 or 52 weeks' therapy in patients with inadequately controlled type 2 diabetes. The addition of vildagliptin 50 mg twice daily to pioglitazone or vildagliptin 50 mg once daily to glimepiride improved HbA(1c) to a significantly greater extent than a thiazolidinedione or glimepiride alone in patients with type 2 diabetes whose disease was inadequately controlled, according to the results of 24-week trials. Oral vildagliptin 50 mg once or twice daily was generally well tolerated in patients with type 2 diabetes. In particular, vildagliptin was associated with a low risk of hypoglycaemia and was weight neutral. Increases in transaminase levels were sometimes observed with a vildagliptin dosage of 100 mg once daily in clinical trials, and liver function should be monitored in patients receiving vildagliptin. However, meta-analyses of clinical trial data suggested that vildagliptin 50 mg once or twice daily was not associated with an increased risk of hepatic adverse events, transaminase elevations ≥3 × the upper limit of normal, pancreatitis, cardiovascular or cerebrovascular events, infections or skin-related toxicity. In conclusion, vildagliptin is an important option for use in combination with metformin, a sulfonylurea or a thiazolidinedione in patients with type 2 diabetes who require combination therapy.
Collapse
|
44
|
Garg SK, Ritchie PJ, Moser EG, Snell-Bergeon JK, Freson BJ, Hazenfield RM. Effects of colesevelam on LDL-C, A1c and GLP-1 levels in patients with type 1 diabetes: a pilot randomized double-blind trial. Diabetes Obes Metab 2011; 13:137-43. [PMID: 21199265 DOI: 10.1111/j.1463-1326.2010.01320.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
AIM colesevelam is indicated to lower low density lipoprotein cholesterol (LDL-C) in hyperlipidaemia and improve glycaemic control in adults with type 2 diabetes. This short-term pilot study evaluates its effects in type 1 diabetes. METHODS this double-blind, randomized, investigator-initiated, single-centred, 12-week pilot study evaluated 40 adults (age = 36.4 ± 9.4 years) with type 1 diabetes (duration = 20.4 ± 8.5 years) and hyperlipidaemia. It was powered to show a treatment difference of >10% LDL-C reduction. Subjects received 3.75 g/day colesevelam (n = 20) or placebo (n = 20) for 12 weeks. LDL-C and haemoglobin A1c (A1c) levels were assessed at screening (week 2), baseline (week 0) and every 4 weeks throughout the treatment duration. Glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP) levels were measured during 4-h meal (Boost Plus, Nestle HealthCare Nutrition Inc., Florham Park, New Jersey, USA) challenge tests (MCT) at baseline and 12 weeks. RESULTS colesevelam treatment resulted in a significant reduction in LDL-C values at 4 weeks [-12.1% (95% CI: -20.1 to -4.1), p = 0.004] which was sustained for the study duration (p = 0.005 at 12 weeks). The treatment group also showed a significant change in A1c from baseline at week 4; however, this was not significant for the study duration. There was a significant median increase in GLP-1 levels during the first 2 h of the baseline MCT in the treated group but no difference at 12 weeks. CONCLUSIONS during this short-term pilot study, colesevelam treatment effectively lowered LDL-C in patients with type 1 diabetes. Improvements in A1c seen at week 4 were not sustained. Effects on glycaemic control in subjects with type 1 diabetes may be related to a postprandial rise in GLP-1 levels and require further clinical study.
Collapse
Affiliation(s)
- S K Garg
- Barbara Davis Center for Childhood Diabetes, University of Colorado Health Sciences Center, Aurora, CO 80045, USA.
| | | | | | | | | | | |
Collapse
|
45
|
Sathananthan A, Man CD, Micheletto F, Zinsmeister AR, Camilleri M, Giesler PD, Laugen JM, Toffolo G, Rizza RA, Cobelli C, Vella A. Common genetic variation in GLP1R and insulin secretion in response to exogenous GLP-1 in nondiabetic subjects: a pilot study. Diabetes Care 2010; 33:2074-6. [PMID: 20805279 PMCID: PMC2928367 DOI: 10.2337/dc10-0200] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE Glucagon-like peptide (GLP)-1 receptor is encoded by GLP1R. The effect of genetic variation at this locus on the response to GLP-1 is unknown. This study assessed the effect of GLP1R polymorphisms on insulin secretion in response to hyperglycemia and to infused GLP-1 in nondiabetic subjects. RESEARCH DESIGN AND METHODS Eighty-eight healthy individuals (aged 26.3 +/- 0.6 years, fasting glucose 4.83 +/- 0.04 mmol/l) were studied using a hyperglycemic clamp. GLP-1 was infused for the last 2 h of the study (0.75 pmol/kg/min over 121-180 min, 1.5 pmol/kg/min over 181-240 min). beta-Cell responsivity (Phi(Total)) was measured using a C-peptide minimal model. The effect of 21 tag single nucleotide polymorphisms (SNPs) in GLP1R on Phi(Total) was examined. RESULTS Two SNPs (rs6923761 and rs3765467) were nominally associated with altered beta-cell responsivity in response to GLP-1 infusion. CONCLUSIONS Variation in GLP1R may alter insulin secretion in response to exogenous GLP-1. Future studies will determine whether such variation accounts for interindividual differences in response to GLP-1-based therapy.
Collapse
Affiliation(s)
- Airani Sathananthan
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic, Rochester, Minnesota, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
46
|
Bock G, Dalla Man C, Micheletto F, Basu R, Giesler PD, Laugen J, Deacon CF, Holst JJ, Toffolo G, Cobelli C, Rizza RA, Vella A. The effect of DPP-4 inhibition with sitagliptin on incretin secretion and on fasting and postprandial glucose turnover in subjects with impaired fasting glucose. Clin Endocrinol (Oxf) 2010; 73:189-96. [PMID: 20039889 PMCID: PMC2908732 DOI: 10.1111/j.1365-2265.2009.03764.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVE Low glucagon-like peptide-1 (GLP-1) concentrations have been observed in impaired fasting glucose (IFG). It is uncertain whether these abnormalities contribute directly to the pathogenesis of IFG and impaired glucose tolerance. Dipeptidyl peptidase-4 (DPP-4) inhibitors raise incretin hormone concentrations enabling an examination of their effects on glucose turnover in IFG. RESEARCH DESIGN AND METHODS We studied 22 subjects with IFG using a double-blinded, placebo-controlled, parallel-group design. At the time of enrollment, subjects ate a standardized meal labelled with [1-(13)C]-glucose. Infused [6-(3)H] glucose enabled measurement of systemic meal appearance (MRa). Infused [6,6-(2)H(2)] glucose enabled measurement of endogenous glucose production (EGP) and glucose disappearance (Rd). Subsequently, subjects were randomized to 100 mg of sitagliptin daily or placebo. After an 8-week treatment period, the mixed meal was repeated. RESULTS As expected, subjects with IFG who received placebo did not experience any change in glucose concentrations. Despite raising intact GLP-1 concentrations, treatment with sitagliptin did not alter either fasting or postprandial glucose, insulin or C-peptide concentrations. Postprandial EGP (18.1 +/- 0.7 vs 17.6 +/- 0.8 micromol/kg per min, P = 0.53), Rd (55.6 +/- 4.3 vs 58.9 +/- 3.3 micromol/kg per min, P = 0.47) and MRa (6639 +/- 377 vs 6581 +/- 316 micromol/kg per 6 h, P = 0.85) were unchanged. Sitagliptin was associated with decreased total GLP-1 implying decreased incretin secretion. CONCLUSIONS DPP-4 inhibition did not alter fasting or postprandial glucose turnover in people with IFG. Low incretin concentrations are unlikely to be involved in the pathogenesis of IFG.
Collapse
Affiliation(s)
- Gerlies Bock
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic College of Medicine, Rochester, MN
| | - Chiara Dalla Man
- Department of Information Engineering, University of Padua, Padua, Italy
| | | | - Rita Basu
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic College of Medicine, Rochester, MN
| | - Paula D Giesler
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic College of Medicine, Rochester, MN
| | - Jeanette Laugen
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic College of Medicine, Rochester, MN
| | - Carolyn F Deacon
- Department of Biomedical Sciences, Panum Institute, Copenhagen, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, Panum Institute, Copenhagen, Denmark
| | - Gianna Toffolo
- Department of Information Engineering, University of Padua, Padua, Italy
| | - Claudio Cobelli
- Department of Information Engineering, University of Padua, Padua, Italy
| | - Robert A Rizza
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic College of Medicine, Rochester, MN
| | - Adrian Vella
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic College of Medicine, Rochester, MN
| |
Collapse
|
47
|
Aaboe K, Knop FK, Vilsbøll T, Deacon CF, Holst JJ, Madsbad S, Krarup T. Twelve weeks treatment with the DPP-4 inhibitor, sitagliptin, prevents degradation of peptide YY and improves glucose and non-glucose induced insulin secretion in patients with type 2 diabetes mellitus. Diabetes Obes Metab 2010; 12:323-33. [PMID: 20380653 DOI: 10.1111/j.1463-1326.2009.01167.x] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
AIM To examine the effects of 12 weeks of treatment with the DPP-4 inhibitor, sitagliptin, on gastrointestinal hormone responses to a standardized mixed meal and beta cell secretory capacity, measured as glucose and non-glucose induced insulin secretion during a hyperglycaemic clamp, in patients with type 2 diabetes. METHOD A double-blinded, placebo-controlled study over 12 weeks in which 24 patients with T2DM were randomized to receive either sitagliptin (Januvia) 100 mg qd or placebo as an add-on therapy to metformin. In week 0, 1 and 12 patients underwent a meal test and a 90-min 20 mM hyperglycaemic clamp with 5 g of l-arginine infusion. Main outcome measure was postprandial total glucagon-like peptide 1 (GLP-1) concentration. Additional measures were insulin and C-peptide, glycaemic control, intact and total peptide YY (PYY) and glucose-dependent insulinotropic polypeptide (GIP), and intact glucagon-like peptide 2 (GLP-2) and GLP-1. RESULTS All patients [sitagliptin n = 12, age: 59.5 (39-64) years, HbA1c: 8.0 (7.3-10.0)%, BMI: 33.2 (29.3-39.4); placebo n = 12, age: 60 (31-72) years, HbA1c: 7.7 (7.1-9.8)%, BMI: 30.7 (25.7-40.5)] [median (range)] completed the trial. Sitagliptin treatment improved glycaemic control, had no effect on total GLP-1, GIP or intact GLP-2, but reduced total PYY and PYY(3- 36), and increased PYY(1- 36) and intact incretin hormones. Sitagliptin improved first and second phases of beta cell secretion and maximal secretory capacity. All effects were achieved after 1 week. No significant changes occurred in the placebo group. CONCLUSION The postprandial responses of total GLP-1 and GIP and intact GLP-2 were unaltered. PYY degradation was prevented. Glucose and non-glucose induced beta cell secretion was improved. There was no difference in responses to sitagliptin between 1 and 12 weeks of treatment.
Collapse
Affiliation(s)
- K Aaboe
- Department of Internal Medicine F, Gentofte Hospital, University of Copenhagen, Denmark
| | | | | | | | | | | | | |
Collapse
|
48
|
Bock G, Dalla Man C, Micheletto F, Basu R, Giesler PD, Laugen J, Deacon CF, Holst JJ, Toffolo G, Cobelli C, Rizza RA, Vella A. The effect of DPP-4 inhibition with sitagliptin on incretin secretion and on fasting and postprandial glucose turnover in subjects with impaired fasting glucose. Clin Endocrinol (Oxf) 2009. [PMID: 20039889 DOI: 10.1111/j.1365-2265.2009.03764] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
OBJECTIVE Low glucagon-like peptide-1 (GLP-1) concentrations have been observed in impaired fasting glucose (IFG). It is uncertain whether these abnormalities contribute directly to the pathogenesis of IFG and impaired glucose tolerance. Dipeptidyl peptidase-4 (DPP-4) inhibitors raise incretin hormone concentrations enabling an examination of their effects on glucose turnover in IFG. RESEARCH DESIGN AND METHODS We studied 22 subjects with IFG using a double-blinded, placebo-controlled, parallel-group design. At the time of enrollment, subjects ate a standardized meal labelled with [1-(13)C]-glucose. Infused [6-(3)H] glucose enabled measurement of systemic meal appearance (MRa). Infused [6,6-(2)H(2)] glucose enabled measurement of endogenous glucose production (EGP) and glucose disappearance (Rd). Subsequently, subjects were randomized to 100 mg of sitagliptin daily or placebo. After an 8-week treatment period, the mixed meal was repeated. RESULTS As expected, subjects with IFG who received placebo did not experience any change in glucose concentrations. Despite raising intact GLP-1 concentrations, treatment with sitagliptin did not alter either fasting or postprandial glucose, insulin or C-peptide concentrations. Postprandial EGP (18.1 +/- 0.7 vs 17.6 +/- 0.8 micromol/kg per min, P = 0.53), Rd (55.6 +/- 4.3 vs 58.9 +/- 3.3 micromol/kg per min, P = 0.47) and MRa (6639 +/- 377 vs 6581 +/- 316 micromol/kg per 6 h, P = 0.85) were unchanged. Sitagliptin was associated with decreased total GLP-1 implying decreased incretin secretion. CONCLUSIONS DPP-4 inhibition did not alter fasting or postprandial glucose turnover in people with IFG. Low incretin concentrations are unlikely to be involved in the pathogenesis of IFG.
Collapse
Affiliation(s)
- Gerlies Bock
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
49
|
Abstract
Epidemiologic studies suggest that postprandial hyperglycemia is more strongly linked to an increased risk for cardiovascular events than fasting or preprandial glucose levels. Although the results of prospective randomized studies proving causation of this finding are mixed, clinicians have given increased attention to target therapy to postprandial glucose than in the past. Rapid-acting insulin analogues, glucagon-like peptide-1 agonists, dipeptidyl peptidase-4 inhibitors, and acarbose all target the postprandial glucose levels. This wide range of therapies allows the clinician to mix and match agents of different classes to target the fasting, preprandial, and postprandial glucose to optimize the daily glucose pattern and reduce the risk of diabetic complications.
Collapse
Affiliation(s)
- Stephen Clement
- Georgetown University Hospital, Division of Endocrinology, Building D, Room 232, 4000 Reservoir Road NW, Washington, DC 20007, USA.
| |
Collapse
|
50
|
Smushkin G, Vella A. Inhibition of dipeptidyl peptidase-4: The mechanisms of action and clinical use of vildagliptin for the management of type 2 diabetes. Diabetes Metab Syndr Obes 2009; 2:83-90. [PMID: 21437121 PMCID: PMC3048000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Postprandial hyperglycemia in type 2 diabetes is characterized by impaired insulin secretion and action, decreased glucose effectiveness and defective suppression of glucagon secretion. Newly available therapies for type 2 diabetes target the pathway of the incretin hormone glucagon-like peptide-1 (GLP-1). Oral inhibitors of dipeptidyl peptidase-4 (DPP-4) raise the level of endogenous GLP-1 by inhibiting its clearance thereby lowering fasting and postprandial glucose concentrations. Unlike compounds which act as agonists of the GLP-1 receptor, DPP-4 inhibitors are not associated with significant effects on gastrointestinal motility, which led to a controversy around the mechanisms responsible for their glucose-lowering effects. Here we review the evidence in regards to the mechanisms whereby DPP-4 inhibitors lower glucose concentrations. Their effects are most likely mediated by an increase in endogenous GLP-1, although additional mechanisms may be involved. The pharmacology, efficacy and safety of vildagliptin, a novel DPP-4 inhibitor, are also discussed.
Collapse
Affiliation(s)
- Galina Smushkin
- Correspondence: Galina Smushkin, Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic, College of Medicine, 200 First ST SW, Rochester, MN55905, USA, Tel + 1 507 284 2784, Fax + 1 507 284 5745, Email
| | | |
Collapse
|