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De Fano M, Malara M, Vermigli C, Murdolo G. Adipose Tissue: A Novel Target of the Incretin Axis? A Paradigm Shift in Obesity-Linked Insulin Resistance. Int J Mol Sci 2024; 25:8650. [PMID: 39201336 PMCID: PMC11354636 DOI: 10.3390/ijms25168650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2024] [Accepted: 08/01/2024] [Indexed: 09/02/2024] Open
Abstract
Adipose tissue (AT) represents a plastic organ that can undergo significant remodeling in response to metabolic demands. With its numerous checkpoints, the incretin system seems to play a significant role in controlling glucose homeostasis and energy balance. The importance of the incretin hormones, namely the glucagon-like peptide-1 (GLP-1) and the glucose-dependent insulinotropic peptide (GIP), in controlling the function of adipose cells has been brought to light by recent studies. Notably, a "paradigm shift" in reevaluating the role of the incretin system in AT as a potential target to treat obesity-linked metabolic disorders resulted from the demonstration that a disruption of the GIP and GLP-1 signaling axis in fat is associated with adiposity-induced insulin-resistance (IR) and/or type 2 diabetes mellitus (T2D). We will briefly discuss the (patho)physiological functions of GLP-1 and GIP signaling in AT in this review, emphasizing their potential impacts on lipid storage, adipogenesis, glucose metabolism and inflammation. We will also address the conundrum with the perturbation of the incretin axis in white or brown fat tissue and the emergence of metabolic disorders. In order to reduce or avoid adiposity-related metabolic complications, we will finally go over a potential scientific rationale for suggesting AT as a novel target for GLP-1 and GIP receptor agonists and co-agonists.
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Affiliation(s)
- Michelantonio De Fano
- Complex Structure of Endocrinology and Metabolism, Department of Medicine, Azienda Ospedaliera Santa Maria Misericordia, Ospedale di Perugia, 06081 Perugia, Italy; (M.M.); (C.V.); (G.M.)
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2
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Das S, Ravi H, Babu A, Banerjee M, Kanagavalli R, Dhanasekaran S, Devi Rajeswari V, Venkatraman G, Ramanathan G. Therapeutic potentials of glucose-dependent insulinotropic polypeptide (GIP) in T2DM: Past, present, and future. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2024; 142:293-328. [PMID: 39059989 DOI: 10.1016/bs.apcsb.2023.12.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/28/2024]
Abstract
Type 2 diabetes mellitus (T2DM) is a worldwide health problem that has raised major concerns to the public health community. This chronic condition typically results from the cell's inability to respond to normal insulin levels. Glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) are the primary incretin hormones secreted from the intestinal tract. While clinical research has extensively explored the therapeutic potential of GLP-1R in addressing various T2DM-related abnormalities, the possibility of GIPR playing an important role in T2DM treatment is still under investigation. Evidence suggests that GIP is involved in the pathophysiology of T2DM. This chapter focuses on examining the role of GIP as a therapeutic molecule in combating T2DM, comparing the past, present, and future scenarios. Our goal is to delve into how GIP may impact pancreatic β-cell function, adipose tissue uptake, and lipid metabolism. Furthermore, we will elucidate the mechanistic functions of GIP and its receptors in relation to other clinical conditions like cardiovascular diseases, non-alcoholic fatty liver diseases, neurodegenerative diseases, and renal disorders. Additionally, this chapter will shed light on the latest advancements in pharmacological management for T2DM, highlighting potential structural modifications of GIP and the repurposing of drugs, while also addressing the challenges involved in bringing GIP-based treatments into clinical practice.
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Affiliation(s)
- Soumik Das
- Department of Bio-Medical Sciences, School of Bio Sciences and Technology, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, India
| | - Harini Ravi
- Department of Bio-Medical Sciences, School of Bio Sciences and Technology, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, India
| | - Achsha Babu
- Department of Bio-Medical Sciences, School of Bio Sciences and Technology, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, India
| | - Manosi Banerjee
- Department of Bio-Medical Sciences, School of Bio Sciences and Technology, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, India
| | - R Kanagavalli
- Department of Bio-Medical Sciences, School of Bio Sciences and Technology, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, India
| | - Sivaraman Dhanasekaran
- School of Energy Technology, Pandit Deendayal Energy University, Knowledge Corridor, Gandhinagar, Gujarat, India
| | - V Devi Rajeswari
- Department of Bio-Medical Sciences, School of Bio Sciences and Technology, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, India
| | - Ganesh Venkatraman
- Department of Bio-Medical Sciences, School of Bio Sciences and Technology, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, India
| | - Gnanasambandan Ramanathan
- Department of Bio-Medical Sciences, School of Bio Sciences and Technology, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, India.
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Guo B, Qi M, Luo X, Guo L, Xu M, Zhang Y, Li Z, Li M, Wu R, Guan T, Liu M, Liu Y. GIP attenuates neuronal oxidative stress by regulating glucose uptake in spinal cord injury of rat. CNS Neurosci Ther 2024; 30:e14806. [PMID: 38887182 PMCID: PMC11183929 DOI: 10.1111/cns.14806] [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: 10/24/2023] [Revised: 05/01/2024] [Accepted: 05/18/2024] [Indexed: 06/20/2024] Open
Abstract
AIM Glucose-dependent insulinotropic polypeptide (GIP) is a ligand of glucose-dependent insulinotropic polypeptide receptor (GIPR) that plays an important role in the digestive system. In recent years, GIP has been regarded as a hormone-like peptide to regulate the local metabolic environment. In this study, we investigated the antioxidant role of GIP on the neuron and explored the possible mechanism. METHODS Cell counting Kit-8 (CCK-8) was used to measure cell survival. TdT-mediated dUTP Nick-End Labeling (TUNEL) was used to detect apoptosis in vitro and in vivo. Reactive oxygen species (ROS) levels were probed with 2', 7'-Dichloro dihydrofluorescein diacetate (DCFH-DA), and glucose intake was detected with 2-NBDG. Immunofluorescence staining and western blot were used to evaluate the protein level in cells and tissues. Hematoxylin-eosin (HE) staining, immunofluorescence staining and tract-tracing were used to observe the morphology of the injured spinal cord. Basso-Beattie-Bresnahan (BBB) assay was used to evaluate functional recovery after spinal cord injury. RESULTS GIP reduced the ROS level and protected cells from apoptosis in cultured neurons and injured spinal cord. GIP facilitated wound healing and functional recovery of the injured spinal cord. GIP significantly improved the glucose uptake of cultured neurons. Meanwhile, inhibition of glucose uptake significantly attenuated the antioxidant effect of GIP. GIP increased glucose transporter 3 (GLUT3) expression via up-regulating the level of hypoxia-inducible factor 1α (HIF-1α) in an Akt-dependent manner. CONCLUSION GIP increases GLUT3 expression and promotes glucose intake in neurons, which exerts an antioxidant effect and protects neuronal cells from oxidative stress both in vitro and in vivo.
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Affiliation(s)
- Beibei Guo
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of Neuroregeneration, Medical SchoolNantong UniversityNantongChina
| | - Mengwei Qi
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology ProductsNantong UniversityNantongChina
| | - Xiaoqian Luo
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology ProductsNantong UniversityNantongChina
| | - Longyu Guo
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology ProductsNantong UniversityNantongChina
| | - Man Xu
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology ProductsNantong UniversityNantongChina
| | - Yufang Zhang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of Neuroregeneration, Medical SchoolNantong UniversityNantongChina
| | - Zhen Li
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology ProductsNantong UniversityNantongChina
| | - Mingxuan Li
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology ProductsNantong UniversityNantongChina
| | - Ronghua Wu
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology ProductsNantong UniversityNantongChina
| | - Tuchen Guan
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology ProductsNantong UniversityNantongChina
| | - Mei Liu
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology ProductsNantong UniversityNantongChina
| | - Yan Liu
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology ProductsNantong UniversityNantongChina
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Öztürk D, Koca AO, Keskin M, Öztürk B, Oğuz EF, Turhan T, Buluş H. Patients who received sleeve gastrectomy have lower plasma osteopontin levels than those who did not. Clinics (Sao Paulo) 2024; 79:100352. [PMID: 38574573 PMCID: PMC10999792 DOI: 10.1016/j.clinsp.2024.100352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Accepted: 03/03/2024] [Indexed: 04/06/2024] Open
Abstract
BACKGROUND The aim of this study was to compare metabolic parameters, plasma Osteopontin (OPN) and Hepatocyte Growth Factor (HGF) levels between Sleeve Gastrectomy (SG) patients in their 6th post-operation month and healthy control patients. METHODS Height, weight, Body Mass Index (BMI) and laboratory parameters of 58 SG patients aged 18‒65 years (Group 1) and 46 healthy control patients (Group 2) were compared. In addition, preoperative and postoperative sixth-month BMI and laboratory parameters of the patients in Group 1 were compared. RESULTS The mean age and gender distributions of the groups were similar (p > 0.05). Mean BMI was 28.9 kg/m2 in Group 1 and 27 kg/m2 in Group 2 (p < 0.01). While plasma HGF levels were similar between both groups, plasma OPN levels were higher in Group 2 (p < 0.001). Fasting plasma glucose, total cholesterol, triglyceride, fasting plasma insulin and insulin resistance values were higher in Group 1, while alanine aminotransferase and aspartate aminotransferase levels were higher in Group 2 (p < 0.05). There was a strong correlation between plasma HGF and OPN levels in Group 1, but not in Group 2 (Rho = 0.805, p < 0.001). CONCLUSION OPN and HGF are promising biomarkers that can be used to better understand and detect problems related to obesity. The fact that patients in the early post-SG period had lower plasma OPN and similar plasma HGF compared to non-surgical patients of similar age and gender with higher BMI may be another favorable and previously unknown metabolic effect of SG.
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Affiliation(s)
- Doğan Öztürk
- University of Health Sciences, Ankara Atatürk Sanatoryum Education and Research Hospital, Department of General Surgery, Ankara, Turkey.
| | - Arzu Or Koca
- University of Health Sciences, Dr. Abdurrahman Yurtaslan Ankara Onkoloji Education and Research Hospital, Department of Endocrinology and Metabolism, Ankara, Turkey
| | - Müge Keskin
- University of Health Sciences, Ankara City Hospital, Department of Endocrinology and Metabolism, Ankara, Turkey
| | - Bülent Öztürk
- University of Health Sciences, Ankara Atatürk Sanatoryum Education and Research Hospital, Department of General Surgery, Ankara, Turkey
| | - Esra Fırat Oğuz
- University of Health Sciences, Ankara City Hospital, Department of Medical Biochemistry, Ankara, Turkey
| | - Turan Turhan
- University of Health Sciences, Ankara City Hospital, Department of Medical Biochemistry, Ankara, Turkey
| | - Hakan Buluş
- University of Health Sciences, Ankara Atatürk Sanatoryum Education and Research Hospital, Department of General Surgery, Ankara, Turkey
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Wang L, Niu X. Immunoregulatory Roles of Osteopontin in Diseases. Nutrients 2024; 16:312. [PMID: 38276550 PMCID: PMC10819284 DOI: 10.3390/nu16020312] [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: 11/17/2023] [Revised: 01/07/2024] [Accepted: 01/18/2024] [Indexed: 01/27/2024] Open
Abstract
Osteopontin (OPN) is a multifunctional protein that plays a pivotal role in the immune system. It is involved in various biological processes, including cell adhesion, migration and survival. The study of the immunomodulatory effects of OPN is of paramount importance due to its potential therapeutic applications. A comprehensive understanding of how OPN regulates the immune response could pave the way for the development of novel treatments for a multitude of diseases, including autoimmune disorders, infectious diseases and cancer. Therefore, in the following paper, we provide a systematic overview of OPN and its immunoregulatory roles in various diseases, laying the foundation for the development of OPN-based therapies in the future.
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Affiliation(s)
- Lebei Wang
- Department of Immunology and Microbiology, Shanghai Institute of Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China;
- College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Xiaoyin Niu
- Department of Immunology and Microbiology, Shanghai Institute of Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China;
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Gasbjerg LS, Rosenkilde MM, Meier JJ, Holst JJ, Knop FK. The importance of glucose-dependent insulinotropic polypeptide receptor activation for the effects of tirzepatide. Diabetes Obes Metab 2023; 25:3079-3092. [PMID: 37551549 DOI: 10.1111/dom.15216] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 06/22/2023] [Accepted: 07/02/2023] [Indexed: 08/09/2023]
Abstract
Tirzepatide is a unimolecular co-agonist of the glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) receptors recently approved for the treatment of type 2 diabetes by the US Food and Drug Administration and the European Medicine Agency. Tirzepatide treatment results in an unprecedented improvement of glycaemic control and lowering of body weight, but the contribution of the GIP receptor-activating component of tirzepatide to these effects is uncertain. In this review, we present the current knowledge about the physiological roles of the incretin hormones GLP-1 and GIP, their receptors, and previous results of co-targeting the two incretin hormone receptors in humans. We also analyse the molecular pharmacological, preclinical and clinical effects of tirzepatide to discuss the role of GIP receptor activation for the clinical effects of tirzepatide. Based on the available literature on the combination of GLP-1 and GIP receptor activation, tirzepatide does not seem to have a classical co-activating mode of action in humans. Rather, in vitro studies of the human GLP-1 and GIP receptors reveal a biased GLP-1 receptor activation profile and GIP receptor downregulation. Therefore, we propose three hypotheses for the mode of action of tirzepatide, which can be addressed in future, elaborate clinical trials.
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Affiliation(s)
- Laerke S Gasbjerg
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
| | - Mette M Rosenkilde
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Juris J Meier
- Department of Internal Medicine, Gastroenterology and Diabetology, Augusta Clinic, Bochum, Germany
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Filip K Knop
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
- Steno Diabetes Center Copenhagen, Herlev, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Campbell JE, Müller TD, Finan B, DiMarchi RD, Tschöp MH, D'Alessio DA. GIPR/GLP-1R dual agonist therapies for diabetes and weight loss-chemistry, physiology, and clinical applications. Cell Metab 2023; 35:1519-1529. [PMID: 37591245 PMCID: PMC10528201 DOI: 10.1016/j.cmet.2023.07.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 06/09/2023] [Accepted: 07/21/2023] [Indexed: 08/19/2023]
Abstract
The incretin system is an essential metabolic axis that regulates postprandial metabolism. The two incretin peptides that enable this effect are the glucose-dependent insulinotropic polypeptide (GIP) and the glucagon-like peptide 1 (GLP-1), which have cognate receptors (GIPR and GLP-1R) on islet β cells as well as in other tissues. Pharmacologic engagement of the GLP-1R is a proven strategy for treating hyperglycemia in diabetes and reducing body weight. Tirzepatide is the first monomeric peptide with dual activity at both incretin receptors now available for clinical use, and in clinical trials it has shown unprecedented effects to reduce blood glucose and body weight. Here, we discuss the foundational science that led to the development of monomeric multi-incretin receptor agonists, culminating in the development of tirzepatide. We also look to the future of this field and comment on how the concept of multi-receptor agonists will continue to progress for the treatment of metabolic disease.
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Affiliation(s)
- Jonathan E Campbell
- Duke Molecular Physiology Institute, Duke University, Durham, NC, USA; Department of Medicine, Division of Endocrinology, Duke University, Durham, NC, USA; Department of Pharmacology and Cancer Biology, Duke University, Durham, NC, USA.
| | - Timo D Müller
- Institute for Diabetes and Obesity, Helmholtz Munich, Neuherberg, Germany; German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Brian Finan
- Novo Nordisk Research Center Indianapolis, Indianapolis, IN, USA
| | | | - Matthias H Tschöp
- German Center for Diabetes Research (DZD), Neuherberg, Germany; Division of Metabolic Diseases, Department of Medicine, Technical University of München, Munich, Germany; Helmholtz Munich, Neuherberg, Germany.
| | - David A D'Alessio
- Duke Molecular Physiology Institute, Duke University, Durham, NC, USA; Department of Medicine, Division of Endocrinology, Duke University, Durham, NC, USA
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8
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Hammoud R, Drucker DJ. Beyond the pancreas: contrasting cardiometabolic actions of GIP and GLP1. Nat Rev Endocrinol 2023; 19:201-216. [PMID: 36509857 DOI: 10.1038/s41574-022-00783-3] [Citation(s) in RCA: 59] [Impact Index Per Article: 59.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/17/2022] [Indexed: 12/14/2022]
Abstract
Glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP1) exhibit incretin activity, meaning that they potentiate glucose-dependent insulin secretion. The emergence of GIP receptor (GIPR)-GLP1 receptor (GLP1R) co-agonists has fostered growing interest in the actions of GIP and GLP1 in metabolically relevant tissues. Here, we update concepts of how these hormones act beyond the pancreas. The actions of GIP and GLP1 on liver, muscle and adipose tissue, in the control of glucose and lipid homeostasis, are discussed in the context of plausible mechanisms of action. Both the GIPR and GLP1R are expressed in the central nervous system, wherein receptor activation produces anorectic effects enabling weight loss. In preclinical studies, GIP and GLP1 reduce atherosclerosis. Furthermore, GIPR and GLP1R are expressed within the heart and immune system, and GLP1R within the kidney, revealing putative mechanisms linking GIP and GLP1R agonism to cardiorenal protection. We interpret the clinical and mechanistic data obtained for different agents that enable weight loss and glucose control for the treatment of obesity and type 2 diabetes mellitus, respectively, by activating or blocking GIPR signalling, including the GIPR-GLP1R co-agonist tirzepatide, as well as the GIPR antagonist-GLP1R agonist AMG-133. Collectively, we update translational concepts of GIP and GLP1 action, while highlighting gaps, areas of uncertainty and controversies meriting ongoing investigation.
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Affiliation(s)
- Rola Hammoud
- Department of Medicine, Lunenfeld-Tanenbaum Research Institute, Mt Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Daniel J Drucker
- Department of Medicine, Lunenfeld-Tanenbaum Research Institute, Mt Sinai Hospital, University of Toronto, Toronto, Ontario, Canada.
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Nguyen A, Khafagy R, Meerasa A, Roshandel D, Paterson AD, Dash S. Insulin Response to Oral Glucose and Cardiometabolic Disease: A Mendelian Randomization Study to Assess Potential Causality. Diabetes 2022; 71:1880-1890. [PMID: 35748295 DOI: 10.2337/db22-0138] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 06/13/2022] [Indexed: 11/13/2022]
Abstract
Mendelian randomization (MR) suggests that postprandial hyperinsulinemia (unadjusted for plasma glucose) increases BMI, but its impact on cardiometabolic disease, a leading cause for mortality and morbidity in people with obesity, is not established. Fat distribution i.e., increased centripetal and/or reduced femoro-gluteal adiposity, is causally associated with and better predicts cardiometabolic disease than BMI. We therefore undertook bidirectional MR to assess the effect of corrected insulin response (CIR) (insulin 30 min after a glucose challenge adjusted for plasma glucose) on BMI, waist-to-hip ratio (WHR), leg fat, type 2 diabetes (T2D), triglyceride (TG), HDL, liver fat, hypertension (HTN), and coronary artery disease (CAD) in people of European descent. Inverse variance-weighted MR suggests a potential causal association between increased CIR and increased BMI (b = 0.048 ± 0.02, P = 0.03), increased leg fat (b = 0.029 ± 0.012, P = 0.01), reduced T2D (b = -0.73 ± 0.15, P = 6 × 10-7, odds ratio [OR] 0.48 [95% CI 0.36-0.64]), reduced TG (b = -0.07 ± 0.02, P = 0.003), and increased HDL (b = 0.04 ± 0.01, P = 0.006) with some evidence of horizontal pleiotropy. CIR had neutral effects on WHR (b = 0.009 ± 0.02, P = 0.69), liver fat (b = -0.08 ± 0.04, P = 0.06), HTN (b = -0.001 ± 0.004, P = 0.7, OR 1.00 [95% CI 0.99-1.01]), and CAD (b = -0.002 ± 0.002, P = 0.48, OR 0.99 [95% CI 0.81-1.21]). T2D decreased CIR (b -0.22 ± 0.04, P = 1.3 × 10-7), with no evidence that BMI, TG, HDL, liver fat, HTN, and CAD modulate CIR. In conclusion, we did not find evidence that increased CIR increases cardiometabolic disease. It might increase BMI with favorable fat distribution, reduce T2D, and improve lipids.
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Affiliation(s)
- Anthony Nguyen
- Department of Medicine, University Health Network, and University of Toronto, Toronto, Canada
| | - Rana Khafagy
- Department of Medicine, University Health Network, and University of Toronto, Toronto, Canada
- Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto, Canada
- Divisions of Epidemiology and Biostatistics, Dalla Lana School of Public Health, University of Toronto, Toronto, Canada
| | - Ameena Meerasa
- Department of Medicine, University Health Network, and University of Toronto, Toronto, Canada
| | - Delnaz Roshandel
- Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto, Canada
| | - Andrew D Paterson
- Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto, Canada
- Divisions of Epidemiology and Biostatistics, Dalla Lana School of Public Health, University of Toronto, Toronto, Canada
| | - Satya Dash
- Department of Medicine, University Health Network, and University of Toronto, Toronto, Canada
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Michałowska J, Miller-Kasprzak E, Seraszek-Jaros A, Mostowska A, Bogdański P. The Link between Three Single Nucleotide Variants of the GIPR Gene and Metabolic Health. Genes (Basel) 2022; 13:genes13091534. [PMID: 36140702 PMCID: PMC9498707 DOI: 10.3390/genes13091534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 08/22/2022] [Accepted: 08/24/2022] [Indexed: 11/26/2022] Open
Abstract
Single nucleotide variants (SNVs) of the GIPR gene have been associated with BMI and type 2 diabetes (T2D), suggesting the role of the variation in this gene in metabolic health. To increase our understanding of this relationship, we investigated the association of three GIPR SNVs, rs11672660, rs2334255 and rs10423928, with anthropometric measurements, selected metabolic parameters, and the risk of excessive body mass and metabolic syndrome (MS) in the Polish population. Normal-weight subjects (n = 340, control group) and subjects with excessive body mass (n = 600, study group) participated in this study. For all participants, anthropometric measurements and metabolic parameters were collected, and genotyping was performed using the high-resolution melting curve analysis. We did not find a significant association between rs11672660, rs2334255 and rs10423928 variants with the risk of being overweight. Differences in metabolic and anthropometric parameters were found for investigated subgroups. An association between rs11672660 and rs10423928 with MS was identified. Heterozygous CT genotype of rs11672660 and AT genotype of rs10423928 were significantly more frequent in the group with MS (OR = 1.38, 95%CI: 1.03–1.85; p = 0.0304 and OR = 1.4, 95%CI: 1.05–1.87; p = 0.0222, respectively). Moreover, TT genotype of rs10423928 was less frequent in the MS group (OR = 0.72, 95%CI: 0.54–0.95; p = 0.0221).
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Affiliation(s)
- Joanna Michałowska
- Department of Treatment of Obesity, Metabolic Disorders and Clinical Dietetics, Poznan University of Medical Sciences, 61-701 Poznan, Poland
- Correspondence:
| | - Ewa Miller-Kasprzak
- Department of Treatment of Obesity, Metabolic Disorders and Clinical Dietetics, Poznan University of Medical Sciences, 61-701 Poznan, Poland
| | - Agnieszka Seraszek-Jaros
- Department of Bioinformatics and Computational Biology, Poznan University of Medical Sciences, 61-701 Poznan, Poland
| | - Adrianna Mostowska
- Department of Biochemistry and Molecular Biology, Poznan University of Medical Sciences, 61-701 Poznan, Poland
| | - Paweł Bogdański
- Department of Treatment of Obesity, Metabolic Disorders and Clinical Dietetics, Poznan University of Medical Sciences, 61-701 Poznan, Poland
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11
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Campbell JE, Beaudry JL, Svendsen B, Baggio LL, Gordon AN, Ussher JR, Wong CK, Gribble FM, D’Alessio DA, Reimann F, Drucker DJ. GIPR Is Predominantly Localized to Nonadipocyte Cell Types Within White Adipose Tissue. Diabetes 2022; 71:1115-1127. [PMID: 35192688 PMCID: PMC7612781 DOI: 10.2337/db21-1166] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 02/16/2022] [Indexed: 02/02/2023]
Abstract
The incretin hormone glucose-dependent insulinotropic polypeptide (GIP) augments glucose-dependent insulin secretion through its receptor expressed on islet β-cells. GIP also acts on adipose tissue; yet paradoxically, both enhanced and reduced GIP receptor (GIPR) signaling reduce adipose tissue mass and attenuate weight gain in response to nutrient excess. Moreover, the precise cellular localization of GIPR expression within white adipose tissue (WAT) remains uncertain. We used mouse genetics to target Gipr expression within adipocytes. Surprisingly, targeting Cre expression to adipocytes using the adiponectin (Adipoq) promoter did not produce meaningful reduction of WAT Gipr expression in Adipoq-Cre:Giprflx/flx mice. In contrast, adenoviral expression of Cre under the control of the cytomegalovirus promoter, or transgenic expression of Cre using nonadipocyte-selective promoters (Ap2/Fabp4 and Ubc) markedly attenuated WAT Gipr expression. Analysis of single-nucleus RNA-sequencing, adipose tissue data sets localized Gipr/GIPR expression predominantly to pericytes and mesothelial cells rather than to adipocytes. Together, these observations reveal that adipocytes are not the major GIPR+ cell type within WAT-findings with mechanistic implications for understanding how GIP and GIP-based co-agonists control adipose tissue biology.
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Affiliation(s)
- Jonathan E. Campbell
- Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, Ontario, Canada
- Duke Molecular Physiology Institute, Duke University, Durham, NC
- Department of Medicine, Division of Endocrinology, Duke University, Durham, NC
- Department of Pharmacology and Cancer Biology, Duke University, Durham, NC
- Corresponding authors: Jonathan E. Campbell, , or Daniel J. Drucker,
| | - Jacqueline L. Beaudry
- Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, Ontario, Canada
| | - Berit Svendsen
- Duke Molecular Physiology Institute, Duke University, Durham, NC
| | - Laurie L. Baggio
- Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, Ontario, Canada
| | - Andrew N. Gordon
- Duke Molecular Physiology Institute, Duke University, Durham, NC
| | - John R. Ussher
- Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, Ontario, Canada
| | - Chi Kin Wong
- Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, Ontario, Canada
| | - Fiona M. Gribble
- Metabolic Research Laboratories, Wellcome Trust MRC Institute of Metabolic Science, Addenbrooke’s Hospital, Cambridge, U.K
| | - David A. D’Alessio
- Duke Molecular Physiology Institute, Duke University, Durham, NC
- Department of Medicine, Division of Endocrinology, Duke University, Durham, NC
| | - Frank Reimann
- Metabolic Research Laboratories, Wellcome Trust MRC Institute of Metabolic Science, Addenbrooke’s Hospital, Cambridge, U.K
| | - Daniel J. Drucker
- Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, Ontario, Canada
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
- Corresponding authors: Jonathan E. Campbell, , or Daniel J. Drucker,
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12
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He X. Glucose-dependent insulinotropic polypeptide and tissue inflammation: Implications for atherogenic cardiovascular disease. EUR J INFLAMM 2022. [DOI: 10.1177/20587392211070402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
Glucose-dependent insulinotropic polypeptide (GIP) has pleiotropic actions on pancreatic endocrine function, adipose tissue lipid metabolism, and skeletal calcium metabolism. Recent data indicate a potential new role for GIP in the pathogenesis of cardiovascular disease. This review focuses on the emerging literature that highlights GIP’s role in inflammation—an established process in the initiation and progression of atherosclerosis. In vasculature tissue, GIP may reduce concentrations of circulating inflammatory cytokines, attenuate vascular endothelial inflammation, and directly limit atherosclerotic vascular damage. Important to recognize is that evidence exists to support both pro- and anti-inflammatory effects of GIP even within the same tissue/cell type. Therefore, future study designs must account for factors such as model heterogeneity, physiological relevance of doses/exposures, potential indirect effects on inflammatory pathways, and the glucose-dependent insulinotropic polypeptide receptor (GIPR) agonist form. Elucidating the specific effects of enhanced GIP signaling in vascular inflammation and atherosclerosis is crucial given the existing widespread use of DPP4 inhibitors and the emergence of dual-incretin receptor agonists for type 2 diabetes treatment.
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Affiliation(s)
- Xiaoming He
- Department of General Surgery, First Affiliated Hospital of Dali University, Dali City, China
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13
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Lindquist P, Gasbjerg LS, Mokrosinski J, Holst JJ, Hauser AS, Rosenkilde MM. The Location of Missense Variants in the Human GIP Gene Is Indicative for Natural Selection. Front Endocrinol (Lausanne) 2022; 13:891586. [PMID: 35846282 PMCID: PMC9277503 DOI: 10.3389/fendo.2022.891586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 05/04/2022] [Indexed: 11/16/2022] Open
Abstract
The intestinal hormone, glucose-dependent insulinotropic polypeptide (GIP), is involved in important physiological functions, including postprandial blood glucose homeostasis, bone remodeling, and lipid metabolism. While mutations leading to physiological changes can be identified in large-scale sequencing, no systematic investigation of GIP missense variants has been performed. Here, we identified 168 naturally occurring missense variants in the human GIP genes from three independent cohorts comprising ~720,000 individuals. We examined amino acid changing variants scattered across the pre-pro-GIP peptide using in silico effect predictions, which revealed that the sequence of the fully processed GIP hormone is more protected against mutations than the rest of the precursor protein. Thus, we observed a highly species-orthologous and population-specific conservation of the GIP peptide sequence, suggestive of evolutionary constraints to preserve the GIP peptide sequence. Elucidating the mutational landscape of GIP variants and how they affect the structural and functional architecture of GIP can aid future biological characterization and clinical translation.
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Affiliation(s)
- Peter Lindquist
- Laboratory for Molecular Pharmacology, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Lærke Smidt Gasbjerg
- Laboratory for Molecular Pharmacology, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jacek Mokrosinski
- Novo Nordisk Research Center Indianapolis, Indianapolis, IN, United States
| | - Jens Juul Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Alexander Sebastian Hauser
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- *Correspondence: Alexander Sebastian Hauser, ; Mette Marie Rosenkilde,
| | - Mette Marie Rosenkilde
- Laboratory for Molecular Pharmacology, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- *Correspondence: Alexander Sebastian Hauser, ; Mette Marie Rosenkilde,
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14
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Al-Rawaf HA, Alghadir AH, Gabr SA. Expression of Circulating MicroRNAs and Myokines and Interactions with Serum Osteopontin in Type 2 Diabetic Patients with Moderate and Poor Glycemic Control: A Biochemical and Molecular Study. BIOMED RESEARCH INTERNATIONAL 2021; 2021:7453000. [PMID: 34917685 PMCID: PMC8670937 DOI: 10.1155/2021/7453000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Accepted: 11/15/2021] [Indexed: 11/18/2022]
Abstract
BACKGROUND Cellular miRNAs are expressed in tissue fluids with sufficient amounts and were identified as potential molecular targets for studying the physiological mechanisms and correlations with many human diseases particularly diabetes. However, molecular-based changes among older adults with diabetes mellitus (DM) are rarely fully elucidated. AIM This study is aimed at identifying circulating miRNAs, which hold the potential to serve as biomarkers for the immune-inflammatory changes in older T2D patients with moderate and poor glycemic control status. In addition, the association of both myokines and osteopontin (OPN) levels with circulating miRNAs was identified. METHODS A total of 80 subjects aged 20-80 years were invited during the period of October 2017-May 2018 to participate in this descriptive cross-sectional study. All subjects were diagnosed with T2D for more than 5 years. Subjects were grouped based on glycemic control (HbA1c values) into two groups: moderate glycemic control (>7-8% HbA1c, no = 30) and poor glycemic control (>8% HbA1c, no = 50), respectively. Diabetic control parameters, fasting blood sugar (FS), HbA1c, fasting insulin (IF), insulin resistance (IR), HOMA-IR, inflammatory cytokines (IL-6, IL-8, IL-18, IL-23, TNF-α, and CRP), osteopontin, and myokines (adropin and irisin) were estimated by colorimetric and immune ELISA assays, respectively. In addition, real-time RT-PCR analysis was performed to evaluate the expression of circulating miRNAs, miR-146a and miR-144, in the serum of all diabetic subjects. RESULTS In this study, T2D patients with poor glycemic control showed a significant increase in the serum levels of IL-6, IL-8, IL-18, IL-23, TNF-α, CRP, and OPN and a reduction in the levels of myokines, adropin and irisin, compared to patients with moderate glycemic control. The results obtained are significantly correlated with the severity of diabetes measured by HbA1c, FS, IF, and HOMA-IR. In addition, baseline expression of miR-146a is significantly reduced and miR-144 is significantly increased in T2D patients with poor glycemic control compared to those with moderate glycemic control. In all diabetic groups, the expression of miR-146a and miR-144 is significantly correlated with diabetic controls, inflammatory cytokines, myokines, and serum levels of OPN. Respective of gender, women with T2D showed more significant change in the expressed miRNAs, inflammatory cytokines, OPN, and serum myokine markers compared to men. ROC analysis identified AUC cutoff values of miR-146a, miR-144, adropin, irisin, and OPN expression levels with considerable specificity and sensitivity which recommends the potential use of adropin, irisin, and OPN as diagnostic biomarkers for diabetes with varying glycemic control status. CONCLUSION In this study, molecular expression of certain microRNA species, such as miR-146a and miR-144, was identified and significantly associated with parameters of disease severity, HbA1c, inflammatory cytokines, myokines, and serum osteopontin in T2D patients with moderate and poor glycemic control. The AUC cutoff values of circulating miRNAs, miR-146a and miR-144; myokines, adropin and irisin; and serum OPN were significantly identified by ROC analysis which additionally recommends the potential use of these biomarkers, miR-146a, miR-144, adropin, irisin, and OPN, as diagnostic biomarkers with considerable specificity and sensitivity for diabetes in patients with varying glycemic control status.
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Affiliation(s)
- Hadeel A. Al-Rawaf
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Saud University, P.O. Box 10219, Riyadh 11433, Saudi Arabia
| | - Ahmad H. Alghadir
- Department of Rehabilitation Sciences, College of Applied Medical Sciences, King Saud University, P.O. Box 10219, Riyadh 11433, Saudi Arabia
| | - Sami A. Gabr
- Department of Rehabilitation Sciences, College of Applied Medical Sciences, King Saud University, P.O. Box 10219, Riyadh 11433, Saudi Arabia
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15
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Nauck MA, Quast DR, Wefers J, Pfeiffer AFH. The evolving story of incretins (GIP and GLP-1) in metabolic and cardiovascular disease: A pathophysiological update. Diabetes Obes Metab 2021; 23 Suppl 3:5-29. [PMID: 34310013 DOI: 10.1111/dom.14496] [Citation(s) in RCA: 135] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/13/2021] [Accepted: 07/13/2021] [Indexed: 11/27/2022]
Abstract
The incretin hormones glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) have their main physiological role in augmenting insulin secretion after their nutrient-induced secretion from the gut. A functioning entero-insular (gut-endocrine pancreas) axis is essential for the maintenance of a normal glucose tolerance. This is exemplified by the incretin effect (greater insulin secretory response to oral as compared to "isoglycaemic" intravenous glucose administration due to the secretion and action of incretin hormones). GIP and GLP-1 have additive effects on insulin secretion. Local production of GIP and/or GLP-1 in islet α-cells (instead of enteroendocrine K and L cells) has been observed, and its significance is still unclear. GLP-1 suppresses, and GIP increases glucagon secretion, both in a glucose-dependent manner. GIP plays a greater physiological role as an incretin. In type 2-diabetic patients, the incretin effect is reduced despite more or less normal secretion of GIP and GLP-1. While insulinotropic effects of GLP-1 are only slightly impaired in type 2 diabetes, GIP has lost much of its acute insulinotropic activity in type 2 diabetes, for largely unknown reasons. Besides their role in glucose homoeostasis, the incretin hormones GIP and GLP-1 have additional biological functions: GLP-1 at pharmacological concentrations reduces appetite, food intake, and-in the long run-body weight, and a similar role is evolving for GIP, at least in animal studies. Human studies, however, do not confirm these findings. GIP, but not GLP-1 increases triglyceride storage in white adipose tissue not only through stimulating insulin secretion, but also by interacting with regional blood vessels and GIP receptors. GIP, and to a lesser degree GLP-1, play a role in bone remodelling. GLP-1, but not GIP slows gastric emptying, which reduces post-meal glycaemic increments. For both GIP and GLP-1, beneficial effects on cardiovascular complications and neurodegenerative central nervous system (CNS) disorders have been observed, pointing to therapeutic potential over and above improving diabetes complications. The recent finding that GIP/GLP-1 receptor co-agonists like tirzepatide have superior efficacy compared to selective GLP-1 receptor agonists with respect to glycaemic control as well as body weight has renewed interest in GIP, which previously was thought to be without any therapeutic potential. One focus of this research is into the long-term interaction of GIP and GLP-1 receptor signalling. A GLP-1 receptor antagonist (exendin [9-39]) and, more recently, a GIP receptor agonist (GIP [3-30] NH2 ) and, hopefully, longer-acting GIP receptor agonists for human use will be helpful tools to shed light on the open questions. A detailed knowledge of incretin physiology and pathophysiology will be a prerequisite for designing more effective incretin-based diabetes drugs.
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Affiliation(s)
- Michael A Nauck
- Diabetes Division, Katholisches Klinikum Bochum, St. Josef Hospital, Ruhr University Bochum, Bochum, Germany
| | - Daniel R Quast
- Diabetes Division, Katholisches Klinikum Bochum, St. Josef Hospital, Ruhr University Bochum, Bochum, Germany
| | - Jakob Wefers
- Diabetes Division, Katholisches Klinikum Bochum, St. Josef Hospital, Ruhr University Bochum, Bochum, Germany
| | - Andreas F H Pfeiffer
- Charité - Universitätsmedizin Berlin, Klinik für Endokrinologie, Stoffwechsel- und Ernährungsmedizin, Berlin, Germany
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16
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Abstract
Glucose-dependent insulinotropic polypeptide (GIP) (also known as gastric inhibitory polypeptide) is a hormone produced in the upper gut and secreted to the circulation in response to the ingestion of foods, especially fatty foods. Growing evidence supports the physiological and pharmacological relevance of GIP in obesity. In an obesity setting, inhibition of endogenous GIP or its receptor leads to decreased energy intake, increased energy expenditure, or both, eventually causing weight loss. Further, supraphysiological dosing of exogenous long-lasting GIP agonists alters energy balance and has a marked antiobesity effect. This remarkable yet paradoxical antiobesity effect is suggested to occur primarily via the brain. The brain is capable of regulating both energy intake and expenditure and plays a critical role in human obesity. In addition, the GIP receptor is widely distributed throughout the brain, including areas responsible for energy homeostasis. Recent studies have uncovered previously underappreciated roles of the GIP receptor in the brain in the context of obesity. This article highlights how the GIP receptor expressed by the brain impacts obesity-related pathogenesis.
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Affiliation(s)
- Makoto Fukuda
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX
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17
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Jujić A, Nilsson PM, Atabaki-Pasdar N, Dieden A, Tuomi T, Franks PW, Holst JJ, Torekov SS, Ravassa S, Díez J, Persson M, Ahlqvist E, Melander O, Gomez MF, Groop L, Magnusson M. Glucose-Dependent Insulinotropic Peptide in the High-Normal Range Is Associated With Increased Carotid Intima-Media Thickness. Diabetes Care 2021; 44:224-230. [PMID: 33208488 PMCID: PMC7612445 DOI: 10.2337/dc20-1318] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 10/11/2020] [Indexed: 02/03/2023]
Abstract
OBJECTIVE While existing evidence supports beneficial cardiovascular effects of glucagon-like peptide 1 (GLP-1), emerging studies suggest that glucose-dependent insulinotropic peptide (GIP) and/or signaling via the GIP receptor may have untoward cardiovascular effects. Indeed, recent studies show that fasting physiological GIP levels are associated with total mortality and cardiovascular mortality, and it was suggested that GIP plays a role in pathogenesis of coronary artery disease. We investigated the associations between fasting and postchallenge GIP and GLP-1 concentrations and subclinical atherosclerosis as measured by mean intima-media thickness in the common carotid artery (IMTmeanCCA) and maximal intima-media thickness in the carotid bifurcation (IMTmaxBulb). RESEARCH DESIGN AND METHODS Participants at reexamination within the Malmö Diet and Cancer-Cardiovascular Cohort study (n = 3,734, mean age 72.5 years, 59.3% women, 10.8% subjects with diabetes, fasting GIP available for 3,342 subjects, fasting GLP-1 available for 3,299 subjects) underwent oral glucose tolerance testing and carotid ultrasound. RESULTS In linear regression analyses, each 1-SD increment of fasting GIP was associated with increased (per mm) IMTmeanCCA (β = 0.010, P = 0.010) and IMTmaxBulb (β = 0.014; P = 0.040) in models adjusted for known risk factors and glucose metabolism. In contrast, each 1-SD increment of fasting GLP-1 was associated with decreased IMTmaxBulb (per mm, β = -0.016, P = 0.014). These associations remained significant when subjects with diabetes were excluded from analyses. CONCLUSIONS In a Swedish elderly population, physiologically elevated levels of fasting GIP are associated with increased IMTmeanCCA, while GLP-1 is associated with decreased IMTmaxBulb, further emphasizing diverging cardiovascular effects of these two incretin hormones.
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Affiliation(s)
- Amra Jujić
- Department of Clinical Sciences, Lund University, Malmö, Sweden .,Department of Cardiology, Skåne University Hospital, Malmö, Sweden.,Lund University Diabetes Centre, Lund University, Malmö, Sweden
| | - Peter M Nilsson
- Department of Clinical Sciences, Lund University, Malmö, Sweden
| | | | - Anna Dieden
- Department of Biomedical Science, Malmö University, Malmö, Sweden
| | - Tiinamaija Tuomi
- Department of Clinical Sciences, Lund University, Malmö, Sweden.,Folkhälsan Research Centre, Biomedicum, and Research Program Unit, Diabetes and Obesity, University of Helsinki, Helsinki, Finland.,Department of Endocrinology, Helsinki University Hospital, Helsinki, Finland.,Finnish Institute of Molecular Medicine, University of Helsinki, Helsinki, Finland
| | - Paul W Franks
- Department of Clinical Sciences, Lund University, Malmö, Sweden.,Department of Nutrition, Harvard School of Public Health, Boston, MA
| | - Jens Juul Holst
- Department of Biomedical Sciences and Novo Nordisk Foundation Center for Basic Metabolic Research, The Panum Institute, University of Copenhagen, Copenhagen, Denmark.,Novo Nordisk Foundation Center for Basic Metabolic Research, The Panum Institute, University of Copenhagen, Copenhagen, Denmark
| | - Signe Sørensen Torekov
- Department of Biomedical Sciences and Novo Nordisk Foundation Center for Basic Metabolic Research, The Panum Institute, University of Copenhagen, Copenhagen, Denmark.,Novo Nordisk Foundation Center for Basic Metabolic Research, The Panum Institute, University of Copenhagen, Copenhagen, Denmark
| | - Susana Ravassa
- Program of Cardiovascular Diseases, Center for Applied Medical Research, University of Navarra, Pamplona, Spain.,CIBERCV, Carlos III Institute of Health, Madrid, Spain.,Instituto de Investigación Sanitaria de Navarra, Pamplona, Spain
| | - Javier Díez
- Program of Cardiovascular Diseases, Center for Applied Medical Research, University of Navarra, Pamplona, Spain.,CIBERCV, Carlos III Institute of Health, Madrid, Spain.,Instituto de Investigación Sanitaria de Navarra, Pamplona, Spain.,Department of Cardiology and Cardiac Surgery and Department of Nephrology, University of Navarra Clinic, Pamplona, Spain
| | | | - Emma Ahlqvist
- Department of Clinical Sciences, Lund University, Malmö, Sweden.,Lund University Diabetes Centre, Lund University, Malmö, Sweden
| | - Olle Melander
- Department of Clinical Sciences, Lund University, Malmö, Sweden
| | - Maria F Gomez
- Department of Clinical Sciences, Lund University, Malmö, Sweden.,Lund University Diabetes Centre, Lund University, Malmö, Sweden
| | - Leif Groop
- Department of Clinical Sciences, Lund University, Malmö, Sweden.,Lund University Diabetes Centre, Lund University, Malmö, Sweden.,Folkhälsan Research Centre, Biomedicum, and Research Program Unit, Diabetes and Obesity, University of Helsinki, Helsinki, Finland
| | - Martin Magnusson
- Department of Clinical Sciences, Lund University, Malmö, Sweden.,Department of Cardiology, Skåne University Hospital, Malmö, Sweden.,Wallenberg Center for Molecular Medicine, Lund University, Lund, Sweden.,Hypertension in Africa Research Team, North-West University Potchefstroom, Potchefstroom, South Africa
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18
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Fu Y, Kaneko K, Lin HY, Mo Q, Xu Y, Suganami T, Ravn P, Fukuda M. Gut Hormone GIP Induces Inflammation and Insulin Resistance in the Hypothalamus. Endocrinology 2020; 161:5865317. [PMID: 32603429 PMCID: PMC7410368 DOI: 10.1210/endocr/bqaa102] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 06/24/2020] [Indexed: 02/08/2023]
Abstract
The hypothalamus plays a critical role in controlling energy balance. High-fat diet (HFD) feeding increases the gene expression of proinflammatory mediators and decreases insulin actions in the hypothalamus. Here, we show that a gut-derived hormone, glucose-dependent insulinotropic polypeptide (GIP), whose levels are elevated during diet-induced obesity, promotes and mediates hypothalamic inflammation and insulin resistance during HFD-induced obesity. Unbiased ribonucleic acid sequencing of GIP-stimulated hypothalami revealed that hypothalamic pathways most affected by intracerebroventricular (ICV) GIP stimulation were related to inflammatory-related responses. Subsequent analysis demonstrated that GIP administered either peripherally or centrally, increased proinflammatory-related factors such as Il-6 and Socs3 in the hypothalamus, but not in the cortex of C57BL/6J male mice. Consistently, hypothalamic activation of IκB kinase-β inflammatory signaling was induced by ICV GIP. Further, hypothalamic levels of proinflammatory cytokines and Socs3 were significantly reduced by an antagonistic GIP receptor (GIPR) antibody and by GIPR deficiency. Additionally, centrally administered GIP reduced anorectic actions of insulin in the brain and diminished insulin-induced phosphorylation of Protein kinase B and Glycogen synthase kinase 3β in the hypothalamus. Collectively, these findings reveal a previously unrecognized role for brain GIP signaling in diet-induced inflammation and insulin resistance in the hypothalamus.
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Affiliation(s)
- Yukiko Fu
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas
- Department of Molecular Medicine and Metabolism, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan
| | - Kentaro Kaneko
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas
| | - Hsiao-Yun Lin
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas
| | - Qianxing Mo
- Dan L Duncan Cancer Center and Center for Cell Gene & Therapy, Baylor College of Medicine, Houston, Texas
- Present address: Department of Biostatistics & Bioinformatics, H. Lee Moffitt Cancer Center & Research Institute, Tampa, Florida 33612
| | - Yong Xu
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas
| | - Takayoshi Suganami
- Department of Molecular Medicine and Metabolism, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan
| | - Peter Ravn
- AstraZeneca, R&D BioPharmaceuticals Unit, Department of Antibody Discovery and Protein Engineering, Cambridge, UK
| | - Makoto Fukuda
- Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas
- Correspondence: Makoto Fukuda, Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA. E-mail:
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19
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Jujić A, Atabaki-Pasdar N, Nilsson PM, Almgren P, Hakaste L, Tuomi T, Berglund LM, Franks PW, Holst JJ, Prasad RB, Torekov SS, Ravassa S, Díez J, Persson M, Melander O, Gomez MF, Groop L, Ahlqvist E, Magnusson M. Glucose-dependent insulinotropic peptide and risk of cardiovascular events and mortality: a prospective study. Diabetologia 2020; 63:1043-1054. [PMID: 31974732 PMCID: PMC7145777 DOI: 10.1007/s00125-020-05093-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 12/18/2019] [Indexed: 12/17/2022]
Abstract
AIMS/HYPOTHESIS Evidence that glucose-dependent insulinotropic peptide (GIP) and/or the GIP receptor (GIPR) are involved in cardiovascular biology is emerging. We hypothesised that GIP has untoward effects on cardiovascular biology, in contrast to glucagon-like peptide 1 (GLP-1), and therefore investigated the effects of GIP and GLP-1 concentrations on cardiovascular disease (CVD) and mortality risk. METHODS GIP concentrations were successfully measured during OGTTs in two independent populations (Malmö Diet Cancer-Cardiovascular Cohort [MDC-CC] and Prevalence, Prediction and Prevention of Diabetes in Botnia [PPP-Botnia]) in a total of 8044 subjects. GLP-1 (n = 3625) was measured in MDC-CC. The incidence of CVD and mortality was assessed via national/regional registers or questionnaires. Further, a two-sample Mendelian randomisation (2SMR) analysis between the GIP pathway and outcomes (coronary artery disease [CAD] and myocardial infarction) was carried out using a GIP-associated genetic variant, rs1800437, as instrumental variable. An additional reverse 2SMR was performed with CAD as exposure variable and GIP as outcome variable, with the instrumental variables constructed from 114 known genetic risk variants for CAD. RESULTS In meta-analyses, higher fasting levels of GIP were associated with risk of higher total mortality (HR[95% CI] = 1.22 [1.11, 1.35]; p = 4.5 × 10-5) and death from CVD (HR[95% CI] 1.30 [1.11, 1.52]; p = 0.001). In accordance, 2SMR analysis revealed that increasing GIP concentrations were associated with CAD and myocardial infarction, and an additional reverse 2SMR revealed no significant effect of CAD on GIP levels, thus confirming a possible effect solely of GIP on CAD. CONCLUSIONS/INTERPRETATION In two prospective, community-based studies, elevated levels of GIP were associated with greater risk of all-cause and cardiovascular mortality within 5-9 years of follow-up, whereas GLP-1 levels were not associated with excess risk. Further studies are warranted to determine the cardiovascular effects of GIP per se.
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Affiliation(s)
- Amra Jujić
- Department of Clinical Sciences Malmö, Lund University, Clinical Research Centre, Hämtställe HS 36, Box 50332, 202 13, Malmö, Sweden
- Department of Cardiology, Skåne University Hospital, Inga Marie Nilssons gata 49, 20502, Malmö, Sweden
| | | | - Peter M Nilsson
- Department of Clinical Sciences Malmö, Lund University, Malmö, Sweden
| | - Peter Almgren
- Department of Clinical Sciences Malmö, Lund University, Malmö, Sweden
- Lund University Diabetes Centre, Lund University, Malmö, Sweden
| | - Liisa Hakaste
- Folkhälsan Research Centre, Biomedicum, Helsinki, Finland
- Research Program Unit, Diabetes and Obesity, University of Helsinki, Helsinki, Finland
- Department of Endocrinology, Helsinki University Hospital, Helsinki, Finland
- Finnish Institute of Molecular Medicine, University of Helsinki, Helsinki, Finland
| | - Tiinamaija Tuomi
- Folkhälsan Research Centre, Biomedicum, Helsinki, Finland
- Research Program Unit, Diabetes and Obesity, University of Helsinki, Helsinki, Finland
- Department of Endocrinology, Helsinki University Hospital, Helsinki, Finland
- Finnish Institute of Molecular Medicine, University of Helsinki, Helsinki, Finland
| | - Lisa M Berglund
- Department of Clinical Sciences Malmö, Lund University, Malmö, Sweden
- Lund University Diabetes Centre, Lund University, Malmö, Sweden
| | - Paul W Franks
- Department of Clinical Sciences Malmö, Lund University, Malmö, Sweden
- Department of Public Health & Clinical Medicine, Umeå University, Umeå, Sweden
- Department of Nutrition, Harvard School of Public Health, Boston, MA, USA
| | - Jens J Holst
- Department of Biomedical Sciences, The Panum Institute, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Rashmi B Prasad
- Department of Clinical Sciences Malmö, Lund University, Malmö, Sweden
- Lund University Diabetes Centre, Lund University, Malmö, Sweden
| | - Signe S Torekov
- Department of Biomedical Sciences, The Panum Institute, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Susana Ravassa
- Program of Cardiovascular Diseases, CIMA, University of Navarra, Pamplona, Spain
- CIBERCV, Carlos III Institute of Health, Madrid, Spain
- Instituto de Investigación Sanitaria de Navarra (IdisNA), Pamplona, Spain
| | - Javier Díez
- Program of Cardiovascular Diseases, CIMA, University of Navarra, Pamplona, Spain
- CIBERCV, Carlos III Institute of Health, Madrid, Spain
- Instituto de Investigación Sanitaria de Navarra (IdisNA), Pamplona, Spain
- Department of Cardiology and Cardiac Surgery, University of Navarra Clinic, Pamplona, Spain
- Department of Nephrology, University of Navarra Clinic, Pamplona, Spain
| | | | - Olle Melander
- Department of Clinical Sciences Malmö, Lund University, Malmö, Sweden
| | - Maria F Gomez
- Department of Clinical Sciences Malmö, Lund University, Malmö, Sweden
- Lund University Diabetes Centre, Lund University, Malmö, Sweden
| | - Leif Groop
- Department of Clinical Sciences Malmö, Lund University, Malmö, Sweden
- Lund University Diabetes Centre, Lund University, Malmö, Sweden
- Department of Endocrinology, Helsinki University Hospital, Helsinki, Finland
| | - Emma Ahlqvist
- Department of Clinical Sciences Malmö, Lund University, Malmö, Sweden
- Lund University Diabetes Centre, Lund University, Malmö, Sweden
| | - Martin Magnusson
- Department of Clinical Sciences Malmö, Lund University, Clinical Research Centre, Hämtställe HS 36, Box 50332, 202 13, Malmö, Sweden.
- Department of Cardiology, Skåne University Hospital, Inga Marie Nilssons gata 49, 20502, Malmö, Sweden.
- Wallenberg Center for Molecular Medicine, Lund University, Malmö, Sweden.
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20
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Gimeno RE, Briere DA, Seeley RJ. Leveraging the Gut to Treat Metabolic Disease. Cell Metab 2020; 31:679-698. [PMID: 32187525 PMCID: PMC7184629 DOI: 10.1016/j.cmet.2020.02.014] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 11/23/2019] [Accepted: 02/20/2020] [Indexed: 02/07/2023]
Abstract
25 years ago, the future of treating obesity and diabetes focused on end organs known to be involved in energy balance and glucose regulation, including the brain, muscle, adipose tissue, and pancreas. Today, the most effective therapies are focused around the gut. This includes surgical options, such as vertical sleeve gastrectomy and Roux-en-Y gastric bypass, that can produce sustained weight loss and diabetes remission but also extends to pharmacological treatments that simulate or amplify various signals that come from the gut. The purpose of this Review is to discuss the wealth of approaches currently under development that seek to further leverage the gut as a source of novel therapeutic opportunities with the hope that we can achieve the effects of surgical interventions with less invasive and more scalable solutions.
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Affiliation(s)
- Ruth E Gimeno
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN 46225, USA
| | - Daniel A Briere
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN 46225, USA
| | - Randy J Seeley
- Department of Surgery, University of Michigan, Ann Arbor, MI 48109, USA.
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21
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Ceddia RP, Collins S. A compendium of G-protein-coupled receptors and cyclic nucleotide regulation of adipose tissue metabolism and energy expenditure. Clin Sci (Lond) 2020; 134:473-512. [PMID: 32149342 PMCID: PMC9137350 DOI: 10.1042/cs20190579] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 02/17/2020] [Accepted: 02/24/2020] [Indexed: 12/15/2022]
Abstract
With the ever-increasing burden of obesity and Type 2 diabetes, it is generally acknowledged that there remains a need for developing new therapeutics. One potential mechanism to combat obesity is to raise energy expenditure via increasing the amount of uncoupled respiration from the mitochondria-rich brown and beige adipocytes. With the recent appreciation of thermogenic adipocytes in humans, much effort is being made to elucidate the signaling pathways that regulate the browning of adipose tissue. In this review, we focus on the ligand-receptor signaling pathways that influence the cyclic nucleotides, cAMP and cGMP, in adipocytes. We chose to focus on G-protein-coupled receptor (GPCR), guanylyl cyclase and phosphodiesterase regulation of adipocytes because they are the targets of a large proportion of all currently available therapeutics. Furthermore, there is a large overlap in their signaling pathways, as signaling events that raise cAMP or cGMP generally increase adipocyte lipolysis and cause changes that are commonly referred to as browning: increasing mitochondrial biogenesis, uncoupling protein 1 (UCP1) expression and respiration.
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Affiliation(s)
- Ryan P Ceddia
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, U.S.A
| | - Sheila Collins
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, U.S.A
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Christensen MB, Gasbjerg LS, Heimbürger SM, Stensen S, Vilsbøll T, Knop FK. GIP's involvement in the pathophysiology of type 2 diabetes. Peptides 2020; 125:170178. [PMID: 31682875 DOI: 10.1016/j.peptides.2019.170178] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Revised: 10/17/2019] [Accepted: 10/17/2019] [Indexed: 02/06/2023]
Abstract
During the past four decades derangements in glucose-dependent insulinotropic polypeptide (GIP) biology has been viewed upon as contributing factors to various parts of the pathophysiology type 2 diabetes. This overview outlines and discusses the impaired insulin responses to GIP as well as the effect of GIP on glucagon secretion and the potential involvement of GIP in the obesity and bone disease associated with type 2 diabetes. As outlined in this review, it is unlikely that the impaired insulinotropic effect of GIP occurs as a primary event in the development of type 2 diabetes, but rather develops once the diabetic state is present and beta cells are unable to maintain normoglycemia. In various models, GIP has effects on glucagon secretion, bone and lipid homeostasis, but whether these effects contribute substantially to the pathophysiology of type 2 diabetes is at present controversial. The review also discusses the substantial uncertainty surrounding the translation of preclinical data relating to the GIP system and outline future research directions.
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Affiliation(s)
- Mikkel B Christensen
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark; Department of Clinical Pharmacology, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark; Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Lærke S Gasbjerg
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark; Department of Biomedicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sebastian M Heimbürger
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Signe Stensen
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark; Department of Biomedicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Tina Vilsbøll
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark; Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Steno Diabetes Center Copenhagen, Gentofte Hospital, Copenhagen, Denmark
| | - Filip K Knop
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark; Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Steno Diabetes Center Copenhagen, Gentofte Hospital, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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23
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Barbosa-Yañez RL, Markova M, Dambeck U, Honsek C, Machann J, Schüler R, Kabisch S, Pfeiffer AFH. Predictive effect of GIPR SNP rs10423928 on glucose metabolism liver fat and adiposity in prediabetic and diabetic subjects. Peptides 2020; 125:170237. [PMID: 31874232 DOI: 10.1016/j.peptides.2019.170237] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Revised: 12/15/2019] [Accepted: 12/18/2019] [Indexed: 11/22/2022]
Abstract
The gastric inhibitory polypeptide receptor (GIPR) regulates postprandial metabolism. In this context GIPR SNP rs10423928 seems toplay an important role in modulating glucose metabolism and insulinsensitivity. However, evidence regarding thisparticular SNP is still vague. In this study, we collected baseline data from four different dietaryintervention studies. We genotyped 424 subjects with prediabetes and 73with diabetes for GIPR SNP rs10423928 and examined its impact on glucosemetabolism, insulin sensitivity and body fat accumulation. We extended previous data by showing that carriers of the A allele withprediabetes displayed increased fasting glucose (p = 0.015). Unexpectedly,A allele carriers showed lower glucose levels 2 h (p = 0.021) after anoral glucose challenge compared to T/T homozygous individuals. A allelecarriers also showed significantly higher insulin sensitivity (p < 0.001)(assessed by Cederholm Index), indicating an enhanced ß-cell response. This study points to a potential protective role for rs10423928 inglucose metabolism and insulin sensitivity in subjects with prediabetes.Further studies are necessary to confirm these results.
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Affiliation(s)
- Renate Luzía Barbosa-Yañez
- Department of Clinical Nutrition, German Institute of Human Nutrition, Potsdam-Rehbruecke, 14558, Nuthetal, Germany; German Center for Diabetes Research (Deutsches Zentrum für Diabetesforschung e.V.), Ingolstädter Landstraße 1, 85764, Neuherberg, Germany; Department of Endocrinology, Diabetes and Nutrition, Campus Benjamin Franklin, Charité University Medicine, Hindenburgdamm 30, 12203, Berlin, Germany.
| | - Mariya Markova
- Department of Clinical Nutrition, German Institute of Human Nutrition, Potsdam-Rehbruecke, 14558, Nuthetal, Germany; German Center for Diabetes Research (Deutsches Zentrum für Diabetesforschung e.V.), Ingolstädter Landstraße 1, 85764, Neuherberg, Germany
| | - Ulrike Dambeck
- Department of Clinical Nutrition, German Institute of Human Nutrition, Potsdam-Rehbruecke, 14558, Nuthetal, Germany; German Center for Diabetes Research (Deutsches Zentrum für Diabetesforschung e.V.), Ingolstädter Landstraße 1, 85764, Neuherberg, Germany; Department of Endocrinology, Diabetes and Nutrition, Campus Benjamin Franklin, Charité University Medicine, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Caroline Honsek
- Department of Clinical Nutrition, German Institute of Human Nutrition, Potsdam-Rehbruecke, 14558, Nuthetal, Germany; German Center for Diabetes Research (Deutsches Zentrum für Diabetesforschung e.V.), Ingolstädter Landstraße 1, 85764, Neuherberg, Germany; Department of Endocrinology, Diabetes and Nutrition, Campus Benjamin Franklin, Charité University Medicine, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Jürgen Machann
- German Center for Diabetes Research (Deutsches Zentrum für Diabetesforschung e.V.), Ingolstädter Landstraße 1, 85764, Neuherberg, Germany; Institute of Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, 72076, Tübingen, Germany; Section on Experimental Radiology, Department of Diagnostic and Interventional Radiology, University Hospital Tübingen, 72076, Tübingen, Germany
| | - Rita Schüler
- Department of Clinical Nutrition, German Institute of Human Nutrition, Potsdam-Rehbruecke, 14558, Nuthetal, Germany; German Center for Diabetes Research (Deutsches Zentrum für Diabetesforschung e.V.), Ingolstädter Landstraße 1, 85764, Neuherberg, Germany
| | - Stefan Kabisch
- Department of Clinical Nutrition, German Institute of Human Nutrition, Potsdam-Rehbruecke, 14558, Nuthetal, Germany; German Center for Diabetes Research (Deutsches Zentrum für Diabetesforschung e.V.), Ingolstädter Landstraße 1, 85764, Neuherberg, Germany; Department of Endocrinology, Diabetes and Nutrition, Campus Benjamin Franklin, Charité University Medicine, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Andreas F H Pfeiffer
- Department of Clinical Nutrition, German Institute of Human Nutrition, Potsdam-Rehbruecke, 14558, Nuthetal, Germany; German Center for Diabetes Research (Deutsches Zentrum für Diabetesforschung e.V.), Ingolstädter Landstraße 1, 85764, Neuherberg, Germany; Department of Endocrinology, Diabetes and Nutrition, Campus Benjamin Franklin, Charité University Medicine, Hindenburgdamm 30, 12203, Berlin, Germany
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24
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El K, Campbell JE. The role of GIP in α-cells and glucagon secretion. Peptides 2020; 125:170213. [PMID: 31785304 PMCID: PMC7580028 DOI: 10.1016/j.peptides.2019.170213] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 11/22/2019] [Accepted: 11/25/2019] [Indexed: 02/07/2023]
Abstract
Glucose-dependent insulinotropic polypeptide (GIP) is an intestinally derived peptide that is secreted in response to feeding. The GIP receptor (GIPR) is expressed in many cell types involved in the regulation of metabolism, including α- and β-cells. Glucagon and insulin exert tremendous control over glucose metabolism. Thus, GIP action in islets strongly dictates metabolic control in the postprandial state. Loss of GIPR activity in β-cells is a characteristic of type 2 diabetes (T2D) which associates with reduced postprandial insulin secretion and hyperglycemia. Less is known about GIPR activity in α-cells or the control of glucagon secretion. GIP stimulates glucagon secretion in a glucose-dependent manner in healthy people, with enhanced activity at lower glycemia. However, GIP stimulates glucagon secretion even at hyperglycemia in people with T2D, suggesting that inappropriate GIPR activity in α-cells contributes to the pathogenesis of T2D. Here, we review the literature describing GIP action and GIPR activity in the α-cell, detailing the basic science that has shaped the view of how GIP regulates glucagon secretion. We also contrast the effects of GIP on glucagon secretion in healthy and T2D people. Finally, we contextualize these observations in light of recent work that redefines the role of glucagon in glucose homeostasis, suggesting that hyperglucagonemia per se does not drive hyperglycemia. As new medications for T2D that incorporate GIPR activity are being developed, it is clear that a better understanding of GIPR activity beyond the β-cell is necessary. This work highlights the importance of focusing on the GIPR in α-cells.
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Affiliation(s)
| | - Jonathan E Campbell
- Duke Molecular Physiology Institute, USA; Department of Medicine, Division of Endocrinology, Duke University, Durham, NC, USA; Department of Pharmacology and Cancer Biology, Duke University, Durham, NC, USA.
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Thondam SK, Cuthbertson DJ, Wilding JPH. The influence of Glucose-dependent Insulinotropic Polypeptide (GIP) on human adipose tissue and fat metabolism: Implications for obesity, type 2 diabetes and Non-Alcoholic Fatty Liver Disease (NAFLD). Peptides 2020; 125:170208. [PMID: 31759125 DOI: 10.1016/j.peptides.2019.170208] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 11/16/2019] [Accepted: 11/19/2019] [Indexed: 12/25/2022]
Abstract
Glucose-dependent insulinotropic polypeptide (GIP) and glucagon like peptide (GLP-1) are the two incretin hormones secreted by the enteroendocrine system in response to nutrient ingestion. Compared with GLP-1, GIP is less well studied as a hormone or as a potential pharmacological treatment. Beyond its insulinotropic effects in the pancreas, GIP has important biological actions in many other tissues but its role in dietary fat metabolism and lipid storage in adipose tissue has been most studied. It is still unclear if such effects of GIP on adipose tissue/fat metabolism are protective or deleterious in the long term. Antagonising GIP actions through genetic and chemical disruption in mice models prevented diet induced obesity and improved insulin sensitivity. Whilst such effects of GIP antagonism are yet to be evaluated in humans, recent studies using combined GIP and GLP-1 agonists have shown weight reduction and improved glycaemic control in people with type 2 diabetes (T2D). Therapeutic manipulation of GIP physiology is intriguing in that both agonists and antagonists of GIP are being investigated to explore their potential weight-reducing and other metabolic benefits in people with obesity, T2D and non-alcoholic fatty liver disease (NAFLD). This review will discuss the physiological effects of GIP on fat metabolism in human adipose and other non-adipose tissues such as liver, pancreas, skeletal muscle and heart, describe where the actions of GIP may contribute to the pathophysiology of obesity, T2D and NAFLD and finally describe the therapeutic implications of GIP antagonism and agonism in these conditions.
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Affiliation(s)
- Sravan K Thondam
- Department of Diabetes and Endocrinology, Liverpool University Hospitals NHS Foundation Trust, Liverpool, United Kingdom
| | - Daniel J Cuthbertson
- Department of Diabetes and Endocrinology, Liverpool University Hospitals NHS Foundation Trust, Liverpool, United Kingdom; Obesity and Endocrinology Research Group, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
| | - John P H Wilding
- Department of Diabetes and Endocrinology, Liverpool University Hospitals NHS Foundation Trust, Liverpool, United Kingdom; Obesity and Endocrinology Research Group, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom.
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26
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Gabe MBN, van der Velden WJC, Smit FX, Gasbjerg LS, Rosenkilde MM. Molecular interactions of full-length and truncated GIP peptides with the GIP receptor - A comprehensive review. Peptides 2020; 125:170224. [PMID: 31809770 DOI: 10.1016/j.peptides.2019.170224] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 11/25/2019] [Accepted: 11/27/2019] [Indexed: 12/17/2022]
Abstract
Enzymatic cleavage of endogenous peptides is a commonly used principle to initiate, modulate and terminate action for instance among cytokines and peptide hormones. The incretin hormones, glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1), and the related hormone glucagon-like peptide-2 (GLP-2) are all rapidly N-terminally truncated with severe loss of intrinsic activity. The most abundant circulating form of full length GIP(1-42) is GIP(3-42) (a dipeptidyl peptidase-4 (DPP-4) product). GIP(1-30)NH2 is another active form resulting from prohormone convertase 2 (PC2) cleavage of proGIP. Like GIP(1-42), GIP(1-30)NH2 is a substrate for DPP-4 generating GIP(3-30)NH2 which, compared to GIP(3-42), binds with higher affinity and very efficiently inhibits GIP receptor (GIPR) activity with no intrinsic activity. Here, we review the action of these four and multiple other N- and C-terminally truncated forms of GIP with an emphasis on molecular pharmacology, i.e. ligand binding, subsequent receptor activation and desensitization. Our overall conclusion is that the N-terminus is essential for receptor activation as GIP N-terminal truncation leads to decreased/lost intrinsic activity and antagonism (similar to GLP-1 and GLP-2), whereas the C-terminal extension of GIP(1-42), as compared to GLP-1, GLP-2 and glucagon (29-33 amino acids), has no apparent impact on the GIPR in vitro, but may play a role for other properties such as stability and tissue distribution. A deeper understanding of the molecular interaction of naturally occurring and designed GIP-based peptides, and their impact in vivo, may contribute to a future therapeutic targeting of the GIP system - either with agonists or with antagonists, or both.
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Affiliation(s)
- Maria Buur Nordskov Gabe
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Wijnand J C van der Velden
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Florent Xavier Smit
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Lærke Smidt Gasbjerg
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark; Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
| | - Mette Marie Rosenkilde
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark.
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GIP as a Potential Therapeutic Target for Atherosclerotic Cardiovascular Disease-A Systematic Review. Int J Mol Sci 2020; 21:ijms21041509. [PMID: 32098413 PMCID: PMC7073149 DOI: 10.3390/ijms21041509] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 02/20/2020] [Accepted: 02/21/2020] [Indexed: 02/06/2023] Open
Abstract
Glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) are gut hormones that are secreted from enteroendocrine L cells and K cells in response to digested nutrients, respectively. They are also referred to incretin for their ability to stimulate insulin secretion from pancreatic beta cells in a glucose-dependent manner. Furthermore, GLP-1 exerts anorexic effects via its actions in the central nervous system. Since native incretin is rapidly inactivated by dipeptidyl peptidase-4 (DPP-4), DPP-resistant GLP-1 receptor agonists (GLP-1RAs), and DPP-4 inhibitors are currently used for the treatment of type 2 diabetes as incretin-based therapy. These new-class agents have superiority to classical oral hypoglycemic agents such as sulfonylureas because of their low risks for hypoglycemia and body weight gain. In addition, a number of preclinical studies have shown the cardioprotective properties of incretin-based therapy, whose findings are further supported by several randomized clinical trials. Indeed, GLP-1RA has been significantly shown to reduce the risk of cardiovascular and renal events in patients with type 2 diabetes. However, the role of GIP in cardiovascular disease remains to be elucidated. Recently, pharmacological doses of GIP receptor agonists (GIPRAs) have been found to exert anti-obesity effects in animal models. These observations suggest that combination therapy of GLP-1R and GIPR may induce superior metabolic and anti-diabetic effects compared with each agonist individually. Clinical trials with GLP-1R/GIPR dual agonists are ongoing in diabetic patients. Therefore, in this review, we summarize the cardiovascular effects of GIP and GIPRAs in cell culture systems, animal models, and humans.
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Tharp WG, Gupta D, Sideleva O, Deacon CF, Holst JJ, Elahi D, Pratley RE. Effects of Pioglitazone on Glucose-Dependent Insulinotropic Polypeptide-Mediated Insulin Secretion and Adipocyte Receptor Expression in Patients With Type 2 Diabetes. Diabetes 2020; 69:146-157. [PMID: 31757794 DOI: 10.2337/db18-1163] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 11/13/2019] [Indexed: 11/13/2022]
Abstract
Incretin hormone dysregulation contributes to reduced insulin secretion and hyperglycemia in patients with type 2 diabetes mellitus (T2DM). Resistance to glucose-dependent insulinotropic polypeptide (GIP) action may occur through desensitization or downregulation of β-cell GIP receptors (GIP-R). Studies in rodents and cell lines show GIP-R expression can be regulated through peroxisome proliferator-activated receptor γ (PPARγ) response elements (PPREs). Whether this occurs in humans is unknown. To test this, we conducted a randomized, double-blind, placebo-controlled trial of pioglitazone therapy on GIP-mediated insulin secretion and adipocyte GIP-R expression in subjects with well-controlled T2DM. Insulin sensitivity improved, but the insulinotropic effect of infused GIP was unchanged following 12 weeks of pioglitazone treatment. In parallel, we observed increased GIP-R mRNA expression in subcutaneous abdominal adipocytes from subjects treated with pioglitazone. Treatment of cultured human adipocytes with troglitazone increased PPARγ binding to GIP-R PPREs. These results show PPARγ agonists regulate GIP-R expression through PPREs in human adipocytes, but suggest this mechanism is not important for regulation of the insulinotropic effect of GIP in subjects with T2DM. Because GIP has antilipolytic and lipogenic effects in adipocytes, the increased GIP-R expression may mediate accretion of fat in patients with T2DM treated with PPARγ agonists.
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Affiliation(s)
- William G Tharp
- Department of Anesthesiology, University of Vermont Medical Center, Larner College of Medicine, University of Vermont, Burlington, VT
| | - Dhananjay Gupta
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Larner College of Medicine, University of Vermont, Burlington, VT
| | - Olga Sideleva
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Larner College of Medicine, University of Vermont, Burlington, VT
| | - Carolyn F Deacon
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens J Holst
- Cardiovascular Division, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Dariush Elahi
- Cardiovascular Division, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Richard E Pratley
- AdventHealth Translational Research Institute for Metabolism and Diabetes, Orlando, FL
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Mosavat M, Omar SZ, Jamalpour S, Tan PC. Serum Glucose-Dependent Insulinotropic Polypeptide (GIP) and Glucagon-Like Peptide-1 (GLP-1) in association with the Risk of Gestational Diabetes: A Prospective Case-Control Study. J Diabetes Res 2020; 2020:9072492. [PMID: 32090124 PMCID: PMC7008251 DOI: 10.1155/2020/9072492] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 12/23/2019] [Accepted: 01/17/2020] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Defects in incretin have been shown to be related to the pathogenesis of type 2 diabetes. Whether such a deficiency happens in gestational diabetes mellitus (GDM) remains to be confirmed. We assessed the association of fasting glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) with GDM. We also studied the longitudinal circulation of these peptides during pregnancy and afterwards. METHODS 53 women with GDM (30 managed with diet only (GDM-diet) and 23 treated with insulin (GDM-insulin)) and 43 pregnant women with normal glucose tolerance (NGDM) were studied, with GIP and GLP-1 levels measured at 24-28 weeks (E1), prior (E2) and after (E3) delivery, and postpuerperium (E4). RESULTS Basal GIP was shown to be low in GDM groups compared to NGDM in E1, and in E4 for GDM-diet. GLP-1 was low in GDM groups during pregnancy and afterwards. At E1, serum GIP and GLP-1 were inversely associated with GDM and participants with lower levels of GIP (<0.23 ng/mL) and GLP-1 (<0.38 ng/mL) had a 6 (95% CI 2.5-14.5)- and 7.6 (95% CI 3.0-19.1)-fold higher risk of developing GDM compared with the higher level, respectively. In the postpuerperium, when there is a drop in β-cell function, participants with previous GDM (pGDM) presented lower GLP-1 (in both GDM subgroups) and lower GIP in GDM-diet subgroup compared to controls. CONCLUSION There is an independent, inverse association between fasting incretins and higher risk of GDM. Furthermore, lowered levels of these peptides may play an important role in the abnormality of glucose regulation following pregnancy.
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Affiliation(s)
- Maryam Mosavat
- Department of Obstetrics & Gynaecology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Siti Zawiah Omar
- Department of Obstetrics & Gynaecology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Sajad Jamalpour
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Peng Chiong Tan
- Department of Obstetrics & Gynaecology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Lin S, Hao G, Lai D, Tian Y, Long M, Lai F, Xiong Y, Ji C, Zang Y. Effect of Oyster Meat Preload on Postmeal Glycemic Control in Healthy Young Adults. J Am Coll Nutr 2019; 39:511-517. [PMID: 31880993 DOI: 10.1080/07315724.2019.1699475] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Objective: Evidence suggests that food preload improves postmeal glycemic profiles, but the effects of marine food are poorly understood. Our study aims to verify the regulating effects of premeal oyster meat (OM) on postprandial blood glucose.Method: Edible parts of the flesh of oyster were prepared for a randomized crossover experiment. After overnight fasting, 20 healthy young men consumed 300 mL of preload drinks with 0 g/kg body weight (BW) (control), 0.1 g/kg BW, and 0.2 g/kg BW. Peripheral blood concentrations of glucose and gastrointestinal hormones were measured before preloading at baseline (0 minutes) and at intervals after the preload and after a preset rice meal. The nutrient composition of OM was analyzed.Results: Compared with other doses, 0.2 g/kg BW OM preload induced higher plasma premeal insulin (p < 0.05), C-peptide (p < 0.05), and glucagon-like peptide-1 (GLP-1; p < 0.05) without altering the glucose concentrations during premeal times. By contrast, 0.2 g/kg BW OM induced less secretion of glucose (p < 0.05) and gastric inhibitory peptide (GIP; p < 0.05), but higher secretion of GLP-1 (p < 0.05) than 0.1 g/kg BW of OM after a meal. During the entire experiment (0-170 minutes), OM reduced the blood glucose (p < 0.05) and GIP (p < 0.05), but increased GLP-1 (p < 0.05). OM was rich in protein (78.4%) and low in fat (6%). Glutamic acid, aspartic acids, glycine, and taurine are the amino acids with high content found in OM.Conclusions: OM preload reduces postmeal glycemia in healthy young people with associated changes in gastrointestinal hormone responses. This effect may be attributed to the rich contents of protein and amino acids of OM.
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Affiliation(s)
- Shuting Lin
- Central Laboratory, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, China
| | - Gengxin Hao
- College of Food and Biological Engineering, Jimei University, Xiamen, China
| | - Dong Lai
- Central Laboratory, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, China
| | - Yan Tian
- Central Laboratory, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, China
| | - Min Long
- Central Laboratory, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, China
| | - Fei Lai
- Central Laboratory, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, China
| | - Yongmei Xiong
- Central Laboratory, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, China
| | - Changfu Ji
- Central Laboratory, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, China
| | - Yuan Zang
- Central Laboratory, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, China
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Incretin Hormones: The Link between Glycemic Index and Cardiometabolic Diseases. Nutrients 2019; 11:nu11081878. [PMID: 31412576 PMCID: PMC6724226 DOI: 10.3390/nu11081878] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 08/07/2019] [Accepted: 08/08/2019] [Indexed: 01/01/2023] Open
Abstract
This review aimed to describe the potential mechanisms by which incretin hormones could mediate the relationship between glycemic index and cardiometabolic diseases. A body of evidence from many studies suggests that low glycemic index (GI) diets reduces the risk for type 2 diabetes and coronary heart disease. In fact, despite the extensive literature on this topic, the mechanisms underlying unfavorable effects of high GI foods on health remain not well defined. The postprandial and hormonal milieu could play a key role in the relationship between GI and cardiovascular risk. Incretin hormones, glucagon-like peptide1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), are important regulators of postprandial homeostasis by amplifying insulin secretory responses. Response of GIP and GLP-1 to GI have been studied more in depth, also by several studies on isomaltulose, which have been taken as an ideal model to investigate the kinetics of incretin secretion in response to foods’ GI. In addition, extrapancreatic effects of these incretin hormones were also recently observed. Emerging from this have been exciting effects on several targets, such as body weight regulation, lipid metabolism, white adipose tissue, cardiovascular system, kidney, and liver, which may importantly affect the health status.
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Asmar M, Asmar A, Simonsen L, Dela F, Holst JJ, Bülow J. GIP-induced vasodilation in human adipose tissue involves capillary recruitment. Endocr Connect 2019; 8:806-813. [PMID: 31063975 PMCID: PMC6590203 DOI: 10.1530/ec-19-0144] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 05/07/2019] [Indexed: 12/11/2022]
Abstract
Glucose-dependent insulinotropic polypeptide (GIP) in combination with hyperinsulinemia increase blood flow and triglyceride clearance in subcutaneous abdominal adipose tissue in lean humans. The present experiments were performed to determine whether the increase involves capillary recruitment. Eight lean healthy volunteers were studied before and after 1 h infusion of GIP or saline during a hyperglycemic-hyperinsulinemic clamp, raising plasma glucose and insulin to postprandial levels. Subcutaneous abdominal adipose tissue blood flow (ATBF) was measured by the 133Xenon clearance technique, and microvascular blood volume was determined by contrast-enhanced ultrasound imaging. During infusion of saline and the clamp, both ATBF (2.7 ± 0.5 mL/min 100 g/tissue) and microvascular blood volume remained unchanged throughout the experiments. During GIP infusion and the clamp, ATBF increased ~fourfold to 11.4 ± 1.9 mL/min 100 g/tissue, P < 0.001. Likewise, the contrast-enhanced ultrasound signal intensity, a measure of the microvascular blood volume, increased significantly 1 h after infusion of GIP and the clamp (P = 0.003), but not in the control experiments. In conclusion, the increase in ATBF during GIP infusion involves recruitment of capillaries in healthy lean subjects, which probably increases the interaction of circulating lipoproteins with lipoprotein lipase, thus promoting adipose tissue lipid uptake.
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Affiliation(s)
- Meena Asmar
- Department of Endocrinology, Bispebjerg and Frederiksberg Hospital, University Hospital of Copenhagen, Copenhagen, Denmark
- Department of Clinical Physiology and Nuclear Medicine, Bispebjerg and Frederiksberg Hospital, University Hospital of Copenhagen, Copenhagen, Denmark
- Correspondence should be addressed to M Asmar:
| | - Ali Asmar
- Department of Clinical Physiology and Nuclear Medicine, Bispebjerg and Frederiksberg Hospital, University Hospital of Copenhagen, Copenhagen, Denmark
- Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, University Hospital of Copenhagen, Copenhagen, Denmark
| | - Lene Simonsen
- Department of Clinical Physiology and Nuclear Medicine, Bispebjerg and Frederiksberg Hospital, University Hospital of Copenhagen, Copenhagen, Denmark
| | - Flemming Dela
- Xlab, Center for Healthy Ageing, University of Copenhagen, Copenhagen, Denmark
- Department of Geriatrics, Bispebjerg and Frederiksberg Hospital, University Hospital of Copenhagen, Copenhagen, Denmark
| | - Jens Juul Holst
- NNF Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens Bülow
- Department of Clinical Physiology and Nuclear Medicine, Bispebjerg and Frederiksberg Hospital, University Hospital of Copenhagen, Copenhagen, Denmark
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
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33
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Inal Kabala S, Yagar H, Ozcan HM. A new biosensor for osteoporosis detection. Prep Biochem Biotechnol 2019; 49:511-520. [DOI: 10.1080/10826068.2019.1587628] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Sevilay Inal Kabala
- Health Services Vocational High School, Kırklareli University, Kırklareli, Turkey
| | - Hulya Yagar
- Department of Chemistry, Faculty of Science, Trakya University, Edirne, Turkey
| | - Hakkı Mevlut Ozcan
- Department of Chemistry, Faculty of Science, Trakya University, Edirne, Turkey
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34
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Mannino GC, Andreozzi F, Sesti G. Pharmacogenetics of type 2 diabetes mellitus, the route toward tailored medicine. Diabetes Metab Res Rev 2019; 35:e3109. [PMID: 30515958 PMCID: PMC6590177 DOI: 10.1002/dmrr.3109] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 11/27/2018] [Accepted: 11/30/2018] [Indexed: 12/11/2022]
Abstract
Type 2 diabetes mellitus (T2DM) is a chronic disease that has reached the levels of a global epidemic. In order to achieve optimal glucose control, it is often necessary to rely on combination therapy of multiple drugs or insulin because uncontrolled glucose levels result in T2DM progression and enhanced risk of complications and mortality. Several antihyperglycemic agents have been developed over time, and T2DM pharmacotherapy should be prescribed based on suitability for the individual patient's characteristics. Pharmacogenetics is the branch of genetics that investigates how our genome influences individual responses to drugs, therapeutic outcomes, and incidence of adverse effects. In this review, we evaluated the pharmacogenetic evidences currently available in the literature, and we identified the top informative genetic variants associated with response to the most common anti-diabetic drugs: metformin, DPP-4 inhibitors/GLP1R agonists, thiazolidinediones, and sulfonylureas/meglitinides. Overall, we found 40 polymorphisms for each drug class in a total of 71 loci, and we examined the possibility of encouraging genetic screening of these variants/loci in order to critically implement decision-making about the therapeutic approach through precision medicine strategies. It is possible then to anticipate that when the clinical practice will take advantage of the genetic information of the diabetic patients, this will provide a useful resource for the prevention of T2DM progression, enabling the identification of the precise drug that is most likely to be effective and safe for each patient and the reduction of the economic impact on a global scale.
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Affiliation(s)
- Gaia Chiara Mannino
- Department of Medical and Surgical SciencesUniversity Magna Graecia of CatanzaroCatanzaroItaly
| | - Francesco Andreozzi
- Department of Medical and Surgical SciencesUniversity Magna Graecia of CatanzaroCatanzaroItaly
| | - Giorgio Sesti
- Department of Medical and Surgical SciencesUniversity Magna Graecia of CatanzaroCatanzaroItaly
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35
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Icer MA, Gezmen-Karadag M. The multiple functions and mechanisms of osteopontin. Clin Biochem 2018; 59:17-24. [PMID: 30003880 DOI: 10.1016/j.clinbiochem.2018.07.003] [Citation(s) in RCA: 317] [Impact Index Per Article: 52.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Revised: 07/03/2018] [Accepted: 07/08/2018] [Indexed: 12/12/2022]
Abstract
Osteopontin (OPN) is a highly phosphorylated glycophosphoprotein having acidic characteristics and rich in aspartic acid. OPN, a multifunctional protein, has important functions on cardiovascular diseases, cancer, diabetes and kidney stone diseases and in the process of inflammation, biomineralization, cell viability and wound healing. Osteopontin acts on organisms by playing a key role in secretion levels of interleukin-10 (IL-10), interleukin-12 (IL-12), interleukin-3 (IL-3), interferon-γ (IFN-γ), integrin αvB3, nuclear factor kappa B (NF-kB), macrophage and T cells, regulating the osteoclast function and affecting CD44 receptors. The aim of the present review is to address majority of different functions of OPN protein which are known, suspected or suggested through the data obtained about this protein yet.
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Affiliation(s)
- Mehmet Arif Icer
- Gazi University, Faculty of Health Sciences, Nutrition and Dietetics Department, 06500 Beşevler, Ankara, Turkey.
| | - Makbule Gezmen-Karadag
- Gazi University, Faculty of Health Sciences, Nutrition and Dietetics Department, 06500 Beşevler, Ankara, Turkey.
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36
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Pfeiffer AFH, Keyhani-Nejad F. High Glycemic Index Metabolic Damage - a Pivotal Role of GIP and GLP-1. Trends Endocrinol Metab 2018; 29:289-299. [PMID: 29602522 DOI: 10.1016/j.tem.2018.03.003] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 02/27/2018] [Accepted: 03/01/2018] [Indexed: 01/16/2023]
Abstract
When glucose-fructose dimers are supplied as the slowly digestible, completely absorbable, low glycemic index (GI) sugar isomaltulose, the detrimental effects of high GI sucrose are avoided. This difference requires the presence of intact glucose-induced insulinotropic peptide receptor (GIPR) and is mediated by the rapid uptake of glucose and the stimulation of GIP release from K cells in the upper small intestine. GIP promotes lipogenesis, fatty liver, insulin resistance, and postprandial inflammation, and reduces fat oxidation in skeletal muscle, partly by hypothalamic interference with energy partitioning and epigenetic programming. GIP is similarly required for the detrimental metabolic effects of other high GI carbohydrates. We therefore propose that the release of GIP in the upper small intestine is an important determinant of the metabolic quality of carbohydrates.
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Affiliation(s)
- Andreas F H Pfeiffer
- Department of Clinical Nutrition, German Institute of Human Nutrition, Nuthetal, Germany; Department for Endocrinology, Diabetes and Nutrition, Charité - University of Medicine, Berlin, Germany; German Center for Diabetes Research, Partner Potsdam and Berlin.
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37
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Gasbjerg LS, Gabe MBN, Hartmann B, Christensen MB, Knop FK, Holst JJ, Rosenkilde MM. Glucose-dependent insulinotropic polypeptide (GIP) receptor antagonists as anti-diabetic agents. Peptides 2018; 100:173-181. [PMID: 29412817 DOI: 10.1016/j.peptides.2017.11.021] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Revised: 11/27/2017] [Accepted: 11/28/2017] [Indexed: 01/07/2023]
Abstract
Glucose-dependent insulinotropic polypeptide (GIP) is an intestinal hormone with a broad range of physiological actions. In the postprandial state, the hormone stimulates insulin secretion and during eu- and hypoglycemia, it stimulates glucagon secretion. In addition, GIP increases triacylglycerol (TAG) uptake in adipose tissue and decreases bone resorption. However, the importance of these actions in humans are not clearly understood as a specific GIP receptor (GIPR) antagonist - an essential tool to study GIP physiology - has been missing. Several different GIPR antagonists have been identified comprising both peptides, vaccines against GIP, GIP antibodies or antibodies against the GIPR. However, most of these have only been tested in rodents. In vitro, N- and C-terminally truncated GIP variants are potent and efficacious GIPR antagonists. Recently, GIP(3-30)NH2, a naturally occurring peptide, was shown to block the GIPR in humans and decrease GIP-induced insulin secretion as well as adipose tissue blood flow and TAG uptake. So far, there are no studies with a GIPR antagonist in patients with type 2 diabetes (T2D), but because the elevations in fasting plasma glucagon and paradoxical postprandial glucagon excursions, seen in patients with T2D, are aggravated by GIP, a GIPR antagonist could partly alleviate this and possibly improve the fasting and postprandial glycemia. Since the majority of patients with T2D are overweight, inhibition of GIP-induced fat deposition may be beneficial as well. Here we summarize the studies of GIPR antagonists and discuss the therapeutic potential of the GIP system in humans.
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Affiliation(s)
- Lærke Smidt Gasbjerg
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Center for Diabetes Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark.
| | - Maria Buur Nordskov Gabe
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Bolette Hartmann
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Mikkel Bring Christensen
- Center for Diabetes Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark; Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Department of Clinical Pharmacology, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Filip Krag Knop
- NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Center for Diabetes Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark; Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens Juul Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Mette Marie Rosenkilde
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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38
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Daniele G, Winnier D, Mari A, Bruder J, Fourcaudot M, Pengou Z, Hansis-Diarte A, Jenkinson C, Tripathy D, Folli F. The potential role of the osteopontin-osteocalcin-osteoprotegerin triad in the pathogenesis of prediabetes in humans. Acta Diabetol 2018; 55:139-148. [PMID: 29151224 PMCID: PMC5816090 DOI: 10.1007/s00592-017-1065-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 10/15/2017] [Indexed: 01/10/2023]
Abstract
AIMS To examine the relationship between hormones involved in bone remodeling and glucose metabolism alterations in prediabetes. METHODS Individuals (n = 43) with NGT (BMI = 31.1 ± 1.1 kg/m2) and individuals (n = 79) with impaired glucose regulation (IGR) (BMI = 31.9 ± 1.2 kg/m2) including subjects with IFG, IGT, and IFG-IGT underwent OGTT and DXA. Osteopontin (OPN), osteocalcin (OCN), osteoprotegerin (OPG), and PTH levels were measured at fasting. Beta-cell function was calculated using C-peptide deconvolution. Dynamic indexes of insulin sensitivity were calculated from OGTT. A subgroup underwent to a euglycemic hyperinsulinemic clamp with 3-3H-glucose to estimate the endogenous glucose production (EGP) and insulin-mediated body glucose disposal (TGD/SSPI). RESULTS OPN was higher in IGR compared to NGT (5.3 ± 0.5 vs. 3.3 ± 0.2 μg/mL; p = 0.008) and in isolated IGT compared to IFG and IFG-IGT (6.3 ± 0.5 vs. 4.5 ± 0.3 and 5.4 ± 0.5 μg/mL; p = 0.02). OCN was similar in IFG and NGT but lower in IGT and IFG-IGT compared to NGT (7.2 ± 0.3 and 5.4 ± 0.2 vs. 8.3 ± 0.3 ng/mL; p < 0.01). OPN was positively correlated with HbA1c, fasting and 2 h plasma glucose and PTH. OCN was negatively correlated with body fat, 2 h plasma glucose, insulin and positively correlated with Stumvoll index. OPG correlated with TGD/SSPI (r = - 0.29; p < 0.05), EGP, and hepatic insulin resistance index in IGR (r = 0.51, r = 0.43; p < 0.01). There was no correlation between PTH and insulin sensitivity or Beta-cell function parameters. CONCLUSIONS In prediabetes, hormones known to be involved in bone remodeling may affect glucose metabolism before overt T2DM occurs with tissue-specific mechanisms.
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Affiliation(s)
- Giuseppe Daniele
- Department of Medicine, Division of Diabetes, University of Texas, Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX, 78229, USA
| | - Deidre Winnier
- Department of Medicine, Division of Diabetes, University of Texas, Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX, 78229, USA
| | - Andrea Mari
- Institute of Neuroscience, National Research Council, Padua, Italy
| | - Jan Bruder
- Department of Medicine, Endocrine division, University of Texas, Health Science Center, San Antonio, TX, USA
| | - Marcel Fourcaudot
- Department of Medicine, Division of Diabetes, University of Texas, Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX, 78229, USA
| | - Zuo Pengou
- Department of Medicine, Division of Diabetes, University of Texas, Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX, 78229, USA
| | - Andrea Hansis-Diarte
- Department of Medicine, Division of Diabetes, University of Texas, Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX, 78229, USA
| | - Christopher Jenkinson
- Department of Medicine, Division of Diabetes, University of Texas, Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX, 78229, USA
| | - Devjit Tripathy
- Department of Medicine, Division of Diabetes, University of Texas, Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX, 78229, USA
| | - Franco Folli
- Department of Medicine, Division of Diabetes, University of Texas, Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX, 78229, USA.
- Universita' degli Studi di Milano, School of Medicine, Dipartimento di Scienze Della Salute, Milan, Italy.
- Department of Medicine, Azienda Socio-Sanitaria Santi Paolo e Carlo, Via A. Di Rudini, 8, 20100, Milan, Italy.
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Sun EWL, Martin AM, Young RL, Keating DJ. The Regulation of Peripheral Metabolism by Gut-Derived Hormones. Front Endocrinol (Lausanne) 2018; 9:754. [PMID: 30662430 PMCID: PMC6328484 DOI: 10.3389/fendo.2018.00754] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 11/27/2018] [Indexed: 12/13/2022] Open
Abstract
Enteroendocrine cells lining the gut epithelium constitute the largest endocrine organ in the body and secrete over 20 different hormones in response to cues from ingested foods and changes in nutritional status. Not only do these hormones convey signals from the gut to the brain via the gut-brain axis, they also act directly on metabolically important peripheral targets in a highly concerted fashion to maintain energy balance and glucose homeostasis. Gut-derived hormones released during fasting tend to be orexigenic and have hyperglycaemic potential. Conversely, gut hormones secreted postprandially generally promote satiety and facilitate glucose clearance. Although some of the metabolic benefits conferred by bariatric surgeries have been ascribed to changes in the secretory profiles of various gut hormones, the therapeutic potential of the enteroendocrine system as a viable target against metabolic diseases remain largely underexploited, except for incretin-mimetics. This review provides a brief overview of the physiological importance and highlights the therapeutic potential of the following gut hormones: serotonin, glucose-dependent insulinotropic peptide, glucagon-like peptide 1, oxyntomodulin, peptide YY, insulin-like peptide 5, and ghrelin.
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Affiliation(s)
- Emily W. L. Sun
- College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
| | - Alyce M. Martin
- College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
| | - Richard L. Young
- Nutrition and Metabolism, South Australian Health and Medical Research Institute, Adelaide, SA, Australia
- Adelaide Medical School, The University of Adelaide, Adelaide, SA, Australia
| | - Damien J. Keating
- College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
- Nutrition and Metabolism, South Australian Health and Medical Research Institute, Adelaide, SA, Australia
- *Correspondence: Damien J. Keating
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40
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Role of osteopontin and its regulation in pancreatic islet. Biochem Biophys Res Commun 2017; 495:1426-1431. [PMID: 29180017 DOI: 10.1016/j.bbrc.2017.11.147] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 11/22/2017] [Indexed: 12/20/2022]
Abstract
Osteopontin (OPN) is involved in various physiological processes and also implicated in multiple pathological states. It has been suggested that OPN may have a role in type 2 diabetes (T2D) by protecting pancreatic islets and interaction with incretins. However, the regulation and function of OPN in islets, especially in humans, remains largely unexplored. In this study, we performed our investigations on both diabetic mouse model SUR1-E1506K+/+ and islets from human donors. We demonstrated that OPN protein, secretion and gene expression was elevated in the diabetic SUR1-E1506K+/+ islets. We also showed that high glucose and incretins simultaneously stimulated islet OPN secretion. In islets from human cadaver donors, OPN gene expression was elevated in diabetic islets, and externally added OPN significantly increased glucose-stimulated insulin secretion (GSIS) from diabetic but not normal glycemic donors. The increase in GSIS by OPN in diabetic human islets was Ca2+ dependent, which was abolished by Ca2+-channel inhibitor isradipine. Furthermore, we also confirmed that OPN promoted cell metabolic activity when challenged by high glucose. These observations provided evidence on the protective role of OPN in pancreatic islets under diabetic condition, and may point to novel therapeutic targets for islet protection in T2D.
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Almgren P, Lindqvist A, Krus U, Hakaste L, Ottosson-Laakso E, Asplund O, Sonestedt E, Prasad RB, Laurila E, Orho-Melander M, Melander O, Tuomi T, Holst JJ, Nilsson PM, Wierup N, Groop L, Ahlqvist E. Genetic determinants of circulating GIP and GLP-1 concentrations. JCI Insight 2017; 2:93306. [PMID: 29093273 DOI: 10.1172/jci.insight.93306] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 09/29/2017] [Indexed: 12/19/2022] Open
Abstract
The secretion of insulin and glucagon from the pancreas and the incretin hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP) from the gastrointestinal tract is essential for glucose homeostasis. Several novel treatment strategies for type 2 diabetes (T2D) mimic GLP-1 actions or inhibit incretin degradation (DPP4 inhibitors), but none is thus far aimed at increasing the secretion of endogenous incretins. In order to identify new potential therapeutic targets for treatment of T2D, we performed a meta-analysis of a GWAS and an exome-wide association study of circulating insulin, glucagon, GIP, and GLP-1 concentrations measured during an oral glucose tolerance test in up to 7,828 individuals. We identified 6 genome-wide significant functional loci associated with plasma incretin concentrations in or near the SLC5A1 (encoding SGLT1), GIPR, ABO, GLP2R, F13A1, and HOXD1 genes and studied the effect of these variants on mRNA expression in pancreatic islet and on metabolic phenotypes. Immunohistochemistry showed expression of GIPR, ABO, and HOXD1 in human enteroendocrine cells and expression of ABO in pancreatic islets, supporting a role in hormone secretion. This study thus provides candidate genes and insight into mechanisms by which secretion and breakdown of GIP and GLP-1 are regulated.
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Affiliation(s)
- Peter Almgren
- Lund University Diabetes Centre, Department of Clinical Sciences, Malmö, Lund University, Skåne University Hospital, Malmö, Sweden
| | - Andreas Lindqvist
- Lund University Diabetes Centre, Department of Clinical Sciences, Malmö, Lund University, Skåne University Hospital, Malmö, Sweden
| | - Ulrika Krus
- Lund University Diabetes Centre, Department of Clinical Sciences, Malmö, Lund University, Skåne University Hospital, Malmö, Sweden
| | - Liisa Hakaste
- Endocrinology, Abdominal Centre, University of Helsinki and Helsinki University Hospital, Helsinki, Finland; Diabetes and Obesity Research Program, University of Helsinki and Folkhälsan Research Center, Helsinki, Finland
| | - Emilia Ottosson-Laakso
- Lund University Diabetes Centre, Department of Clinical Sciences, Malmö, Lund University, Skåne University Hospital, Malmö, Sweden
| | - Olof Asplund
- Lund University Diabetes Centre, Department of Clinical Sciences, Malmö, Lund University, Skåne University Hospital, Malmö, Sweden
| | - Emily Sonestedt
- Lund University Diabetes Centre, Department of Clinical Sciences, Malmö, Lund University, Skåne University Hospital, Malmö, Sweden
| | - Rashmi B Prasad
- Lund University Diabetes Centre, Department of Clinical Sciences, Malmö, Lund University, Skåne University Hospital, Malmö, Sweden
| | - Esa Laurila
- Lund University Diabetes Centre, Department of Clinical Sciences, Malmö, Lund University, Skåne University Hospital, Malmö, Sweden
| | - Marju Orho-Melander
- Lund University Diabetes Centre, Department of Clinical Sciences, Malmö, Lund University, Skåne University Hospital, Malmö, Sweden
| | - Olle Melander
- Lund University Diabetes Centre, Department of Clinical Sciences, Malmö, Lund University, Skåne University Hospital, Malmö, Sweden
| | - Tiinamaija Tuomi
- Endocrinology, Abdominal Centre, University of Helsinki and Helsinki University Hospital, Helsinki, Finland; Diabetes and Obesity Research Program, University of Helsinki and Folkhälsan Research Center, Helsinki, Finland.,Finnish Institute for Molecular Medicine, University of Helsinki, Helsinki, Finland
| | - Jens Juul Holst
- Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Peter M Nilsson
- Clinical Research Unit Medicine, Department of Internal Medicine, and Department of Clinical Sciences, Malmö, Lund University, Skåne University Hospital, Malmö, Sweden
| | - Nils Wierup
- Lund University Diabetes Centre, Department of Clinical Sciences, Malmö, Lund University, Skåne University Hospital, Malmö, Sweden
| | - Leif Groop
- Lund University Diabetes Centre, Department of Clinical Sciences, Malmö, Lund University, Skåne University Hospital, Malmö, Sweden.,Finnish Institute for Molecular Medicine, University of Helsinki, Helsinki, Finland
| | - Emma Ahlqvist
- Lund University Diabetes Centre, Department of Clinical Sciences, Malmö, Lund University, Skåne University Hospital, Malmö, Sweden
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Molecular mechanisms of ROS production and oxidative stress in diabetes. Biochem J 2017; 473:4527-4550. [PMID: 27941030 DOI: 10.1042/bcj20160503c] [Citation(s) in RCA: 528] [Impact Index Per Article: 75.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 10/07/2016] [Accepted: 10/10/2016] [Indexed: 12/18/2022]
Abstract
Oxidative stress and chronic inflammation are known to be associated with the development of metabolic diseases, including diabetes. Oxidative stress, an imbalance between oxidative and antioxidative systems of cells and tissues, is a result of over production of oxidative-free radicals and associated reactive oxygen species (ROS). One outcome of excessive levels of ROS is the modification of the structure and function of cellular proteins and lipids, leading to cellular dysfunction including impaired energy metabolism, altered cell signalling and cell cycle control, impaired cell transport mechanisms and overall dysfunctional biological activity, immune activation and inflammation. Nutritional stress, such as that caused by excess high-fat and/or carbohydrate diets, promotes oxidative stress as evident by increased lipid peroxidation products, protein carbonylation and decreased antioxidant status. In obesity, chronic oxidative stress and associated inflammation are the underlying factors that lead to the development of pathologies such as insulin resistance, dysregulated pathways of metabolism, diabetes and cardiovascular disease through impaired signalling and metabolism resulting in dysfunction to insulin secretion, insulin action and immune responses. However, exercise may counter excessive levels of oxidative stress and thus improve metabolic and inflammatory outcomes. In the present article, we review the cellular and molecular origins and significance of ROS production, the molecular targets and responses describing how oxidative stress affects cell function including mechanisms of insulin secretion and action, from the point of view of possible application of novel diabetic therapies based on redox regulation.
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Thondam SK, Daousi C, Wilding JPH, Holst JJ, Ameen GI, Yang C, Whitmore C, Mora S, Cuthbertson DJ. Glucose-dependent insulinotropic polypeptide promotes lipid deposition in subcutaneous adipocytes in obese type 2 diabetes patients: a maladaptive response. Am J Physiol Endocrinol Metab 2017; 312:E224-E233. [PMID: 28073779 DOI: 10.1152/ajpendo.00347.2016] [Citation(s) in RCA: 34] [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: 09/21/2016] [Revised: 11/28/2016] [Accepted: 01/02/2017] [Indexed: 12/19/2022]
Abstract
Glucose-dependent insulinotropic polypeptide (GIP) beyond its insulinotropic effects may regulate postprandial lipid metabolism. Whereas the insulinotropic action of GIP is known to be impaired in type 2 diabetes mellitus (T2DM), its adipogenic effect is unknown. We hypothesized that GIP is anabolic in human subcutaneous adipose tissue (SAT) promoting triacylglycerol (TAG) deposition through reesterification of nonesterified fatty acids (NEFA), and this effect may differ according to obesity status or glucose tolerance. Twenty-three subjects categorized into four groups, normoglycemic lean (n = 6), normoglycemic obese (n = 6), obese with impaired glucose regulation (IGR; n = 6), and obese T2DM (n = 5), participated in a double-blind, randomized, crossover study involving a hyperglycemic clamp with a 240-min GIP infusion (2 pmol·kg-1·min-1) or normal saline. Insulin, NEFA, SAT-TAG content, and gene expression of key lipogenic enzymes were determined before and immediately after GIP/saline infusions. GIP lowered NEFA concentrations in the obese T2DM group despite diminished insulinotropic activity (mean NEFA AUC0-4 h ± SE, 41,992 ± 9,843 µmol·l-1·min-1 vs. 71,468 ± 13,605 with placebo, P = 0.039, 95% CI: 0.31-0.95). Additionally, GIP increased SAT-TAG in obese T2DM (1.78 ± 0.4 vs 0.86 ± 0.1-fold with placebo, P = 0.043, 95% CI: 0.1-1.8). Such effect with GIP was not observed in other three groups despite greater insulinotropic activity. Reduction in NEFA concentration with GIP correlated with adipose tissue insulin resistance for all subjects (Pearson, r = 0.56, P = 0.005). There were no significant gene expression changes in key SAT lipid metabolism enzymes. In conclusion, GIP appears to promote fat accretion and thus may exacerbate obesity and insulin resistance in T2DM.
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Affiliation(s)
- Sravan K Thondam
- Obesity and Endocrinology Research Group, University Hospital Aintree, Liverpool, United Kingdom
| | - Christina Daousi
- Obesity and Endocrinology Research Group, University Hospital Aintree, Liverpool, United Kingdom
| | - John P H Wilding
- Obesity and Endocrinology Research Group, University Hospital Aintree, Liverpool, United Kingdom
- Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
| | - Jens J Holst
- NovoNordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Gulizar I Ameen
- Department of Cellular and Molecular Physiology University of Liverpool, Liverpool, United Kingdom; and
| | - Chenjing Yang
- Department of Cellular and Molecular Physiology University of Liverpool, Liverpool, United Kingdom; and
| | - Catherine Whitmore
- Obesity and Endocrinology Research Group, University Hospital Aintree, Liverpool, United Kingdom
| | - Silvia Mora
- Department of Cellular and Molecular Physiology University of Liverpool, Liverpool, United Kingdom; and
| | - Daniel J Cuthbertson
- Obesity and Endocrinology Research Group, University Hospital Aintree, Liverpool, United Kingdom
- Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
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Osteopontin Affects Insulin Vesicle Localization and Ca2+ Homeostasis in Pancreatic Beta Cells from Female Mice. PLoS One 2017; 12:e0170498. [PMID: 28107503 PMCID: PMC5249066 DOI: 10.1371/journal.pone.0170498] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Accepted: 12/15/2016] [Indexed: 02/06/2023] Open
Abstract
Type 2 diabetic patients suffer from insulin resistance and reduced insulin secretion. Osteopontin (OPN), a versatile protein expressed in several tissues throughout the body including the islets of Langerhans, has previously been implicated in the development of insulin resistance. Here we have investigated the role of OPN in insulin secretion using an OPN knock out mouse model (OPN-/-). Ultra-structural analyzes of islets from OPN-/- and WT mice indicated weaker cell-cell connections between the islet cells in the OPN-/- mouse compared to WT. Analysis of the insulin granule distribution in the beta cells showed that although OPN-/- and WT beta cells have the same number of insulin granules OPN-/- beta cells have significantly fewer docked granules. Both OPN-/- and WT islets displayed synchronized Ca2+ oscillations indicative of an intact beta cell communication. OPN-/- islets displayed higher intracellular Ca2+ concentrations when stimulated with 16.7 mM glucose than WT islets and the initial dip upon elevated glucose concentrations (which is associated with Ca2+ uptake into ER) was significantly lower in these islets. Glucose-induced insulin secretion was similar in OPN-/- and WT islets. Likewise, non-fasted blood glucose levels were the same in both groups. In summary, deletion of OPN results in several minor beta-cell defects that can be compensated for in a healthy system.
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Talat MA, Sherief LM, El-Saadany HF, Rass AA, Saleh RM, Sakr MMH. The Role of Osteopontin in the Pathogenesis and Complications of Type 1 Diabetes Mellitus in Children. J Clin Res Pediatr Endocrinol 2016; 8:399-404. [PMID: 27353561 PMCID: PMC5197997 DOI: 10.4274/jcrpe.3082] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
OBJECTIVE Type 1 diabetes mellitus (T1DM) is the most common chronic metabolic disorder of childhood and adolescence. Osteopontin plays a significant role in the development and progression of several autoimmune diseases. Moreover, osteopontin promotes adipose tissue inflammation, dysfunction, and insulin resistance. To investigate the levels of serum osteopontin in pediatric patients with T1DM and to explore if these levels have a role in the prediction of diabetes complications. METHODS This was a case-control study conducted at the Endocrinology unit of the Children's Hospital of Zagazig University in Egypt, from October 2014 to December 2015. Sixty patients with T1DM and 60 healthy subjects were enrolled. A detailed medical history was taken from all patients/parents. A full clinical examination including ophthalmoscopy was performed on all patients. Fasting blood glucose, hemoglobin A1c (HbA1c), urine albumin/creatinine ratio, and serum osteopontin levels were also determined in all subjects. RESULTS Patients with T1DM had significantly higher serum osteopontin levels compared with controls (mean ± standard deviation: 13.7±3.4 μg/L vs. 8.9±2.9 μg/L, p<0.001). Also, serum osteopontin concentrations were higher in patients with microalbuminuria than in patients with normal albumin excretion rate and in the control group. Similarly, those who had retinal disease had higher osteopontin concentrations than those without (16.8±2 vs. 12.4±3 mg/L; p=0.005). Serum osteopontin levels correlated with a diagnosis of T1DM, and in diabetic patients, correlated with higher systolic and diastolic blood pressure, body mass index values and with lower high density lipoprotein values, diagnosis of retinopathy, and microalbuminuria. No correlation was found between osteopontin levels and HbA1c, insulin dose, co-medications, and diabetes duration in T1DM patients. The association between high osteopontin levels and T1DM was independent from all confounders. CONCLUSION This study shows that increased osteopontin levels are independently associated with T1DM in pediatric patients and supports the hypothesis that osteopontin may have a role in the prediction of microvascular diabetes complications.
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Affiliation(s)
- Mohamed A. Talat
- Zagazig University Faculty of Medicine, Department of Pediatrics, Zagazig, Egypt
,* Address for Correspondence: Zagazig University Faculty of Medicine, Department of Pediatrics, Zagazig, Egypt Phone: +20 122 994 27 69 E-mail:
| | | | | | - Anwar Ahmed Rass
- Zagazig University Faculty of Medicine, Department of Pediatrics, Zagazig, Egypt
| | - Rabab M. Saleh
- Zagazig University Faculty of Medicine, Department of Pediatrics, Zagazig, Egypt
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Pujadas G, Drucker DJ. Vascular Biology of Glucagon Receptor Superfamily Peptides: Mechanistic and Clinical Relevance. Endocr Rev 2016; 37:554-583. [PMID: 27732058 DOI: 10.1210/er.2016-1078] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Regulatory peptides produced in islet and gut endocrine cells, including glucagon, glucagon-like peptide-1 (GLP-1), GLP-2, and glucose-dependent insulinotropic polypeptide, exert actions with considerable metabolic importance and translational relevance. Although the clinical development of GLP-1 receptor agonists and dipeptidyl peptidase-4 inhibitors has fostered research into how these hormones act on the normal and diseased heart, less is known about the actions of these peptides on blood vessels. Here we review the effects of these peptide hormones on normal blood vessels and highlight their vascular actions in the setting of experimental and clinical vascular injury. The cellular localization and signal transduction properties of the receptors for glucagon, GLP-1, GLP-2, and glucose-dependent insulinotropic polypeptide are discussed, with emphasis on endothelial cells and vascular smooth muscle cells. The actions of these peptides on the control of blood flow, blood pressure, angiogenesis, atherosclerosis, and vascular inflammation are reviewed with a focus on elucidating direct and indirect mechanisms of action. How these peptides traverse the blood-brain barrier is highlighted, with relevance to the use of GLP-1 receptor agonists to treat obesity and neurodegenerative disorders. Wherever possible, we compare actions identified in cell lines and primary cell culture with data from preclinical studies and, when available, results of human investigation, including studies in subjects with diabetes, obesity, and cardiovascular disease. Throughout the review, we discuss pitfalls, limitations, and challenges of the existing literature and highlight areas of controversy and uncertainty. The increasing use of peptide-based therapies for the treatment of diabetes and obesity underscores the importance of understanding the vascular biology of peptide hormone action.
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Affiliation(s)
- Gemma Pujadas
- Department of Medicine, Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto, ON M5G 1X5, Canada
| | - Daniel J Drucker
- Department of Medicine, Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto, ON M5G 1X5, Canada
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The blunted effect of glucose-dependent insulinotropic polypeptide in subcutaneous abdominal adipose tissue in obese subjects is partly reversed by weight loss. Nutr Diabetes 2016; 6:e208. [PMID: 27136446 PMCID: PMC4895376 DOI: 10.1038/nutd.2016.15] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Revised: 03/10/2016] [Accepted: 03/20/2016] [Indexed: 01/07/2023] Open
Abstract
Background: Glucose-dependent insulinotropic polypeptide (GIP) appears to have impaired effect on subcutaneous abdominal adipose tissue metabolism in obese subjects. The aim of the present study was to examine whether weight loss may reverse the impaired effect of GIP on subcutaneous abdominal adipose tissue in obese subjects. Methods: Five obese males participated in a 12-week weight loss program, which consisted of caloric restriction (800 Cal day−1) followed by 4 weeks of weight-maintenance diet. Before and after weight loss, subcutaneous adipose tissue lipid metabolism was studied by conducting regional measurements of arterio-venous plasma concentrations of metabolites and blood flow (adipose tissue blood flow, ATBF) across a segment of the abdominal adipose tissue in the fasting state and during GIP infusion (1.5 pmol kg−1 min−1) in combination with a hyperinsulinemic–hyperglycemic clamp. Results: After weight loss (7.5±0.8 kg), glucose tolerance and insulin sensitivity increased significantly as expected. No significant differences were seen in basal ATBF before (1.3±0.4 ml min−1 100 g tissue−1) and after weight loss (2.1±0.4 ml min−1 100 g tissue)−1; however, a tendency to increase was seen. After weight loss, GIP infusion increased ATBF significantly (3.2±0.1 ml min−1 100 g tissue−1) whereas there was no increase before weight loss. Triacylglycerol (TAG) uptake did not change after weight loss. Baseline free fatty acid (FFA) and glycerol output increased significantly after weight loss, P<0.001. During the clamp period, FFA and glycerol output declined significantly, P<0.05, with no differences before and after weight loss. Weight loss increased glucose uptake and decreased FFA/glycerol ratio during the clamp period, P<0.05. Conclusions: In obese subjects, weight loss, induced by calorie restriction, improves the blunted effect of GIP on subcutaneous abdominal adipose tissue metabolism.
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Finan B, Müller TD, Clemmensen C, Perez-Tilve D, DiMarchi RD, Tschöp MH. Reappraisal of GIP Pharmacology for Metabolic Diseases. Trends Mol Med 2016; 22:359-376. [DOI: 10.1016/j.molmed.2016.03.005] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 03/15/2016] [Accepted: 03/17/2016] [Indexed: 12/31/2022]
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Omar B, Ahlkvist L, Yamada Y, Seino Y, Ahrén B. Incretin hormone receptors are required for normal beta cell development and function in female mice. Peptides 2016; 79:58-65. [PMID: 27020250 DOI: 10.1016/j.peptides.2016.03.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 03/01/2016] [Accepted: 03/23/2016] [Indexed: 02/07/2023]
Abstract
The incretin hormones, glucose dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1), potentiate insulin secretion and are responsible for the majority of insulin secretion that occurs after a meal. They may also, however, have a fundamental role in pancreatic beta cell development and function, independently of their role in potentiating insulin secretion after a meal. This has led to observations that a loss of GIP or GLP-1 action affects normal beta cell function, however each one of the incretin hormones may compensate when the action of the other is lost and therefore the overall impact of the incretin hormones on beta cell function is not known. We therefore utilized a mouse line deficient in both the GLP-1 and GIP receptor genes, the double incretin receptor knockout (DIRKO), to determine the consequences of a lifelong, complete lack of incretin hormone action on beta cell function, in vivo, in intact animals. We found that DIRKO mice displayed impaired glucose tolerance and insulin secretion in response to both oral glucose and mixed meal tolerance tests compared to wild-type mice. Assessment of beta cell function using the hyperglycemic clamp technique revealed an 80% decrease in first phase insulin response in DIRKO mice, but a normal second phase insulin secretion. A similar decline was seen when wild-type mice were given acute intravenous injection of glucose together with the GLP-1 receptor antagonist Ex9-39. Ex vivo assessments of the pancreas revealed significantly fewer islets in the pancreata of DIRKO mice despite no differences in total pancreatic mass. Insulin secretion from isolated islets of DIRKO mice was impaired to a similar extent to that seen during the hyperglycemic clamp. Insulin secretion in wild-type islets was impaired by acute treatment with Ex9-39 to a similar extent as the in vivo intravenous glucose tolerance tests. In conclusion, a loss of the action of both incretin hormones results in direct impairment of beta cell function both in vivo and in vitro in a process that appears to be independent of the intestinally secreted incretin hormones. We therefore conclude that the incretin hormones together significantly impact both beta-cell function and beta-cell development.
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Affiliation(s)
- Bilal Omar
- Department of Clinical Sciences, Medicine, Lund University, Sölvegatan 19, 22184 Lund, Sweden.
| | - Linda Ahlkvist
- Department of Clinical Sciences, Medicine, Lund University, Sölvegatan 19, 22184 Lund, Sweden
| | - Yuchiro Yamada
- Graduate School of Medicine, Akita University, Akita, Japan
| | - Yutaka Seino
- Yutaka Seino Distinguished Center for Diabetes Research, Kensai Electric Power Medical Research Institute, Kobe, Japan
| | - Bo Ahrén
- Department of Clinical Sciences, Medicine, Lund University, Sölvegatan 19, 22184 Lund, Sweden
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