1
|
Haberman N, Cheung R, Pizza G, Cvetesic N, Nagy D, Maude H, Blazquez L, Lenhard B, Cebola I, Rutter GA, Martinez-Sanchez A. Liver kinase B1 (LKB1) regulates the epigenetic landscape of mouse pancreatic beta cells. FASEB J 2024; 38:e23885. [PMID: 39139039 DOI: 10.1096/fj.202401078r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2024] [Revised: 07/26/2024] [Accepted: 08/02/2024] [Indexed: 08/15/2024]
Abstract
Liver kinase B1 (LKB1/STK11) is an important regulator of pancreatic β-cell identity and function. Elimination of Lkb1 from the β-cell results in improved glucose-stimulated insulin secretion and is accompanied by profound changes in gene expression, including the upregulation of several neuronal genes. The mechanisms through which LKB1 controls gene expression are, at present, poorly understood. Here, we explore the impact of β cell-selective deletion of Lkb1 on chromatin accessibility in mouse pancreatic islets. To characterize the role of LKB1 in the regulation of gene expression at the transcriptional level, we combine these data with a map of islet active transcription start sites and histone marks. We demonstrate that LKB1 elimination from β-cells results in widespread changes in chromatin accessibility, correlating with changes in transcript levels. Changes occurred in hundreds of promoter and enhancer regions, many of which were close to neuronal genes. We reveal that dysregulated enhancers are enriched in binding motifs for transcription factors (TFs) important for β-cell identity, such as FOXA, MAFA or RFX6, and we identify microRNAs (miRNAs) that are regulated by LKB1 at the transcriptional level. Overall, our study provides important new insights into the epigenetic mechanisms by which LKB1 regulates β-cell identity and function.
Collapse
Affiliation(s)
- Nejc Haberman
- MRC London Institute of Medical Sciences, London, UK
- Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, UK
- Division of Neuroscience, Department of Brain Sciences, Imperial College London, London, UK
| | - Rebecca Cheung
- Section of Cell Biology and Functional Genomics, Faculty of Medicine, Imperial College London, London, UK
| | - Grazia Pizza
- Section of Cell Biology and Functional Genomics, Faculty of Medicine, Imperial College London, London, UK
| | - Nevena Cvetesic
- MRC London Institute of Medical Sciences, London, UK
- Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, UK
| | - Dorka Nagy
- Section of Genetics and Genomics, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
- National Heart and Lung Institute, Imperial College London, London, UK
| | - Hannah Maude
- Section of Genetics and Genomics, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Lorea Blazquez
- Department of Neurosciences, Biogipuzkoa Health Research Institute, San Sebastián, Spain
- Ikerbasque, Basque Foundation for Science, Bilbao, Spain
- CIBERNED, ISCIII (CIBER, Carlos III Institute, Spanish Ministry of Sciences and Innovation), Madrid, Spain
| | - Boris Lenhard
- MRC London Institute of Medical Sciences, London, UK
- Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, UK
| | - Inês Cebola
- Section of Genetics and Genomics, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Guy A Rutter
- Section of Cell Biology and Functional Genomics, Faculty of Medicine, Imperial College London, London, UK
- Research Centre of the Centre Hospitalier de l'Université de Montréal (CRCHUM), Faculté de Médecine, Université de Montréal, Montréal, Quebec, Canada
- Lee Kong Chian Medical School, Nanyang Technological University, Singapore, Singapore
| | - Aida Martinez-Sanchez
- Section of Cell Biology and Functional Genomics, Faculty of Medicine, Imperial College London, London, UK
| |
Collapse
|
2
|
Lemche E, Killick R, Mitchell J, Caton PW, Choudhary P, Howard JK. Molecular mechanisms linking type 2 diabetes mellitus and late-onset Alzheimer's disease: A systematic review and qualitative meta-analysis. Neurobiol Dis 2024; 196:106485. [PMID: 38643861 DOI: 10.1016/j.nbd.2024.106485] [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: 06/30/2023] [Revised: 03/18/2024] [Accepted: 03/23/2024] [Indexed: 04/23/2024] Open
Abstract
Research evidence indicating common metabolic mechanisms through which type 2 diabetes mellitus (T2DM) increases risk of late-onset Alzheimer's dementia (LOAD) has accumulated over recent decades. The aim of this systematic review is to provide a comprehensive review of common mechanisms, which have hitherto been discussed in separate perspectives, and to assemble and evaluate candidate loci and epigenetic modifications contributing to polygenic risk linkages between T2DM and LOAD. For the systematic review on pathophysiological mechanisms, both human and animal studies up to December 2023 are included. For the qualitative meta-analysis of genomic bases, human association studies were examined; for epigenetic mechanisms, data from human studies and animal models were accepted. Papers describing pathophysiological studies were identified in databases, and further literature gathered from cited work. For genomic and epigenomic studies, literature mining was conducted by formalised search codes using Boolean operators in search engines, and augmented by GeneRif citations in Entrez Gene, and other sources (WikiGenes, etc.). For the systematic review of pathophysiological mechanisms, 923 publications were evaluated, and 138 gene loci extracted for testing candidate risk linkages. 3 57 publications were evaluated for genomic association and descriptions of epigenomic modifications. Overall accumulated results highlight insulin signalling, inflammation and inflammasome pathways, proteolysis, gluconeogenesis and glycolysis, glycosylation, lipoprotein metabolism and oxidation, cell cycle regulation or survival, autophagic-lysosomal pathways, and energy. Documented findings suggest interplay between brain insulin resistance, neuroinflammation, insult compensatory mechanisms, and peripheral metabolic dysregulation in T2DM and LOAD linkage. The results allow for more streamlined longitudinal studies of T2DM-LOAD risk linkages.
Collapse
Affiliation(s)
- Erwin Lemche
- Section of Cognitive Neuropsychiatry and Centre for Neuroimaging Sciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, De Crespigny Park, London SE5 8AF, United Kingdom.
| | - Richard Killick
- Section of Old Age Psychiatry, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology & Neuroscience, King's College London, De Crespigny Park, London SE5 8AF, United Kingdom
| | - Jackie Mitchell
- Department of Basic and Clinical Neurosciences, Maurice Wohl CIinical Neurosciences Institute, Institute of Psychiatry, Psychology & Neuroscience, King's College London, 125 Coldharbour Lane, London SE5 9NU, United Kingdom
| | - Paul W Caton
- Diabetes Research Group, School of Life Course Sciences, King's College London, Hodgkin Building, Guy's Campus, London SE1 1UL, United Kingdom
| | - Pratik Choudhary
- Diabetes Research Group, Weston Education Centre, King's College London, 10 Cutcombe Road, London SE5 9RJ, United Kingdom
| | - Jane K Howard
- School of Cardiovascular and Metabolic Medicine & Sciences, Hodgkin Building, Guy's Campus, King's College London, Great Maze Pond, London SE1 1UL, United Kingdom
| |
Collapse
|
3
|
Rivera Nieves AM, Wauford BM, Fu A. Mitochondrial bioenergetics, metabolism, and beyond in pancreatic β-cells and diabetes. Front Mol Biosci 2024; 11:1354199. [PMID: 38404962 PMCID: PMC10884328 DOI: 10.3389/fmolb.2024.1354199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Accepted: 01/17/2024] [Indexed: 02/27/2024] Open
Abstract
In Type 1 and Type 2 diabetes, pancreatic β-cell survival and function are impaired. Additional etiologies of diabetes include dysfunction in insulin-sensing hepatic, muscle, and adipose tissues as well as immune cells. An important determinant of metabolic health across these various tissues is mitochondria function and structure. This review focuses on the role of mitochondria in diabetes pathogenesis, with a specific emphasis on pancreatic β-cells. These dynamic organelles are obligate for β-cell survival, function, replication, insulin production, and control over insulin release. Therefore, it is not surprising that mitochondria are severely defective in diabetic contexts. Mitochondrial dysfunction poses challenges to assess in cause-effect studies, prompting us to assemble and deliberate the evidence for mitochondria dysfunction as a cause or consequence of diabetes. Understanding the precise molecular mechanisms underlying mitochondrial dysfunction in diabetes and identifying therapeutic strategies to restore mitochondrial homeostasis and enhance β-cell function are active and expanding areas of research. In summary, this review examines the multidimensional role of mitochondria in diabetes, focusing on pancreatic β-cells and highlighting the significance of mitochondrial metabolism, bioenergetics, calcium, dynamics, and mitophagy in the pathophysiology of diabetes. We describe the effects of diabetes-related gluco/lipotoxic, oxidative and inflammation stress on β-cell mitochondria, as well as the role played by mitochondria on the pathologic outcomes of these stress paradigms. By examining these aspects, we provide updated insights and highlight areas where further research is required for a deeper molecular understanding of the role of mitochondria in β-cells and diabetes.
Collapse
Affiliation(s)
- Alejandra María Rivera Nieves
- Diabetes Center of Excellence, University of Massachusetts Chan Medical School, Worcester, MA, United States
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Brian Michael Wauford
- Diabetes Center of Excellence, University of Massachusetts Chan Medical School, Worcester, MA, United States
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Accalia Fu
- Diabetes Center of Excellence, University of Massachusetts Chan Medical School, Worcester, MA, United States
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, United States
| |
Collapse
|
4
|
Nguyen-Tu MS, Harris J, Martinez-Sanchez A, Chabosseau P, Hu M, Georgiadou E, Pollard A, Otero P, Lopez-Noriega L, Leclerc I, Sakamoto K, Schmoll D, Smith DM, Carling D, Rutter GA. Opposing effects on regulated insulin secretion of acute vs chronic stimulation of AMP-activated protein kinase. Diabetologia 2022; 65:997-1011. [PMID: 35294578 PMCID: PMC9076735 DOI: 10.1007/s00125-022-05673-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 12/13/2021] [Indexed: 11/26/2022]
Abstract
AIMS/HYPOTHESIS Although targeted in extrapancreatic tissues by several drugs used to treat type 2 diabetes, the role of AMP-activated protein kinase (AMPK) in the control of insulin secretion is still debatable. Previous studies have used pharmacological activators of limited selectivity and specificity, and none has examined in primary pancreatic beta cells the actions of the latest generation of highly potent and specific activators that act via the allosteric drug and metabolite (ADaM) site. METHODS AMPK was activated acutely in islets isolated from C57BL6/J mice, and in an EndoC-βH3 cell line, using three structurally distinct ADaM site activators (991, PF-06409577 and RA089), with varying selectivity for β1- vs β2-containing complexes. Mouse lines expressing a gain-of-function mutation in the γ1 AMPK subunit (D316a) were generated to examine the effects of chronic AMPK stimulation in the whole body, or selectively in the beta cell. RESULTS Acute (1.5 h) treatment of wild-type mouse islets with 991, PF-06409577 or RA089 robustly stimulated insulin secretion at high glucose concentrations (p<0.01, p<0.05 and p<0.001, respectively), despite a lowering of glucose-induced intracellular free Ca2+ dynamics in response to 991 (AUC, p<0.05) and to RA089 at the highest dose (25 μmol/l) at 5.59 min (p<0.05). Although abolished in the absence of AMPK, the effects of 991 were observed in the absence of the upstream kinase, liver kinase B1, further implicating 'amplifying' pathways. In marked contrast, chronic activation of AMPK, either globally or selectively in the beta cell, achieved using a gain-of-function mutant, impaired insulin release in vivo (p<0.05 at 15 min following i.p. injection of 3 mmol/l glucose) and in vitro (p<0.01 following incubation of islets with 17 mmol/l glucose), and lowered glucose tolerance (p<0.001). CONCLUSIONS/INTERPRETATION AMPK activation exerts complex, time-dependent effects on insulin secretion. These observations should inform the design and future clinical use of AMPK modulators.
Collapse
Affiliation(s)
- Marie-Sophie Nguyen-Tu
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Joseph Harris
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Aida Martinez-Sanchez
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Pauline Chabosseau
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Ming Hu
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Eleni Georgiadou
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Alice Pollard
- MRC- London Institute of Medical Sciences, Imperial College London, London, UK
- Structure Biophysics and Fragments, Discovery Sciences, AstraZeneca R&D, Cambridge, UK
| | - Pablo Otero
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Livia Lopez-Noriega
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Isabelle Leclerc
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Kei Sakamoto
- Novo Nordisk Center for Basic Metabolic Research, Copenhagen, Denmark
| | - Dieter Schmoll
- Sanofi-Aventis Deutschland GmbH, Frankfurt am Main, Germany
| | - David M Smith
- Emerging Innovations Unit, Discovery Sciences, AstraZeneca R&D , Cambridge, UK
| | - David Carling
- MRC- London Institute of Medical Sciences, Imperial College London, London, UK
| | - Guy A Rutter
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK.
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Republic of Singapore.
- CR-CHUM, University of Montréal, Montréal, QC, Canada.
| |
Collapse
|
5
|
Sarnobat D, Moffett RC, Flatt PR, Tarasov AI. Effects of first-line diabetes therapy with biguanides, sulphonylurea and thiazolidinediones on the differentiation, proliferation and apoptosis of islet cell populations. J Endocrinol Invest 2022; 45:95-103. [PMID: 34191257 PMCID: PMC8741670 DOI: 10.1007/s40618-021-01620-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 06/17/2021] [Indexed: 12/13/2022]
Abstract
AIMS Metformin, rosiglitazone and sulfonylureas enhance either insulin action or secretion and thus have been used extensively as early stage anti-diabetic medication, independently of the aetiology of the disease. When administered to newly diagnosed diabetes patients, these drugs produce variable results. Here, we examined the effects of the three early stage oral hypoglycaemic agents in mice with diabetes induced by multiple low doses of streptozotocin, focusing specifically on the developmental biology of pancreatic islets. METHODS Streptozotocin-treated diabetic mice expressing a fluorescent reporter specifically in pancreatic islet α-cells were administered the biguanide metformin (100 mg/kg), thiazolidinedione rosiglitazone (10 mg/kg), or sulfonylurea tolbutamide (20 mg/kg) for 10 days. We assessed the impact of the treatment on metabolic status of the animals as well as on the morphology, proliferative potential and transdifferentiation of pancreatic islet cells, using immunofluorescence. RESULTS The effect of the therapy on the islet cells varied depending on the drug and included enhanced pancreatic islet β-cell proliferation, in case of metformin and rosiglitazone; de-differentiation of α-cells and β-cell apoptosis with tolbutamide; increased relative number of β-cells and bi-hormonal insulin + glucagon + cells with metformin. These effects were accompanied by normalisation of food and fluid intake with only minor effects on glycaemia at the low doses of the agents employed. CONCLUSIONS Our data suggest that metformin and rosiglitazone attenuate the depletion of the β-cell pool in the streptozotocin-induced diabetes, whereas tolbutamide exacerbates the β-cell apoptosis, but is likely to protect β-cells from chronic hyperglycaemia by directly elevating insulin secretion.
Collapse
Affiliation(s)
- D Sarnobat
- School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, BT52 1SA, Northern Ireland, UK
| | - R C Moffett
- School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, BT52 1SA, Northern Ireland, UK
| | - P R Flatt
- School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, BT52 1SA, Northern Ireland, UK
| | - A I Tarasov
- School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, BT52 1SA, Northern Ireland, UK.
| |
Collapse
|
6
|
PEGylated AdipoRon derivatives improve glucose and lipid metabolism under insulinopenic and high-fat diet conditions. J Lipid Res 2021; 62:100095. [PMID: 34214600 PMCID: PMC8327158 DOI: 10.1016/j.jlr.2021.100095] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 06/17/2021] [Indexed: 12/19/2022] Open
Abstract
The pleiotropic actions of adiponectin in improving cell survival and metabolism have motivated the development of small-molecule therapeutic agents for treating diabetes and lipotoxicity. AdipoRon is a synthetic agonist of the adiponectin receptors, yet is limited by its poor solubility and bioavailability. In this work, we expand on the protective effects of AdipoRon in pancreatic β-cells and examine how structural modifications could affect the activity, pharmacokinetics, and bioavailability of this small molecule. We describe a series of AdipoRon analogs containing amphiphilic ethylene glycol (PEG) chains. Among these, AdipoRonPEG5 induced pleiotropic effects in mice under insulinopenic and high-fat diet (HFD) conditions. While both AdipoRon and AdipoRonPEG5 substantially attenuate palmitate-induced lipotoxicity in INS-1 cells, only AdipoRonPEG5 treatment is accompanied by a significant reduction in cytotoxic ceramides. In vivo, AdipoRonPEG5 can substantially reduce pancreatic, hepatic, and serum ceramide species, with a concomitant increase in the corresponding sphingoid bases and improves insulin sensitivity of mice under HFD feeding conditions. Furthermore, hyperglycemia in streptozotocin (STZ)-induced insulinopenic adiponectin-null mice is also attenuated upon AdipoRonPEG5 treatment. Our results suggest that AdipoRonPEG5 is more effective in reducing ceramides and dihydroceramides in the liver of HFD-fed mice than AdipoRon, consistent with its potent activity in activating ceramidase in vitro in INS-1 cells. Additionally, these results indicate that the beneficial effects of AdipoRonPEG5 can be partially attributed to improved pharmacokinetics as compared with AdipoRon, thus suggesting that further derivatization may improve affinity and tissue-specific targeting.
Collapse
|
7
|
Rodríguez C, Muñoz M, Contreras C, Prieto D. AMPK, metabolism, and vascular function. FEBS J 2021; 288:3746-3771. [PMID: 33825330 DOI: 10.1111/febs.15863] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 03/04/2021] [Accepted: 04/04/2021] [Indexed: 12/12/2022]
Abstract
Adenosine monophosphate-activated protein kinase (AMPK) is a cellular energy sensor activated during energy stress that plays a key role in maintaining energy homeostasis. This ubiquitous signaling pathway has been implicated in multiple functions including mitochondrial biogenesis, redox regulation, cell growth and proliferation, cell autophagy and inflammation. The protective role of AMPK in cardiovascular function and the involvement of dysfunctional AMPK in the pathogenesis of cardiovascular disease have been highlighted in recent years. In this review, we summarize and discuss the role of AMPK in the regulation of blood flow in response to metabolic demand and the basis of the AMPK physiological anticontractile, antioxidant, anti-inflammatory, and antiatherogenic actions in the vascular system. Investigations by others and us have demonstrated the key role of vascular AMPK in the regulation of endothelial function, redox homeostasis, and inflammation, in addition to its protective role in the hypoxia and ischemia/reperfusion injury. The pathophysiological implications of AMPK involvement in vascular function with regard to the vascular complications of metabolic disease and the therapeutic potential of AMPK activators are also discussed.
Collapse
Affiliation(s)
- Claudia Rodríguez
- Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
| | - Mercedes Muñoz
- Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
| | - Cristina Contreras
- Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
| | - Dolores Prieto
- Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
| |
Collapse
|
8
|
Alanentalo T, Hahn M, Willekens SMA, Ahlgren U. Mesoscopic Optical Imaging of the Pancreas-Revisiting Pancreatic Anatomy and Pathophysiology. Front Endocrinol (Lausanne) 2021; 12:633063. [PMID: 33746904 PMCID: PMC7969990 DOI: 10.3389/fendo.2021.633063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 01/07/2021] [Indexed: 11/24/2022] Open
Abstract
The exocrine-endocrine multipart organization of the pancreas makes it an exceedingly challenging organ to analyze, quantitatively and spatially. Both in rodents and humans, estimates of the pancreatic cellular composition, including beta-cell mass, has been largely relying on the extrapolation of 2D stereological data originating from limited sample volumes. Alternatively, they have been obtained by low resolution non-invasive imaging techniques providing little detail regarding the anatomical organization of the pancreas and its cellular and/or molecular make up. In this mini-review, the state of the art and the future potential of currently existing and emerging high-resolution optical imaging techniques working in the mm-cm range with μm resolution, here referred to as mesoscopic imaging approaches, will be discussed regarding their contribution toward a better understanding of pancreatic anatomy both in normal conditions and in the diabetic setting. In particular, optical projection tomography (OPT) and light sheet fluorescence microscopy (LSFM) imaging of the pancreas and their associated tissue processing and computational analysis protocols will be discussed in the light of their current capabilities and future potential to obtain more detailed 3D-spatial, quantitative, and molecular information of the pancreas.
Collapse
|
9
|
Cruz AM, Partridge KM, Malekizadeh Y, Vlachaki Walker JM, Weightman Potter PG, Pye KR, Shaw SJ, Ellacott KLJ, Beall C. Brain Permeable AMP-Activated Protein Kinase Activator R481 Raises Glycaemia by Autonomic Nervous System Activation and Amplifies the Counterregulatory Response to Hypoglycaemia in Rats. Front Endocrinol (Lausanne) 2021; 12:697445. [PMID: 34975743 PMCID: PMC8718766 DOI: 10.3389/fendo.2021.697445] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 11/15/2021] [Indexed: 11/13/2022] Open
Abstract
AIM We evaluated the efficacy of a novel brain permeable "metformin-like" AMP-activated protein kinase activator, R481, in regulating glucose homeostasis. MATERIALS AND METHODS We used glucose sensing hypothalamic GT1-7 neuronal cells and pancreatic αTC1.9 α-cells to examine the effect of R481 on AMPK pathway activation and cellular metabolism. Glucose tolerance tests and hyperinsulinemic-euglycemic and hypoglycemic clamps were used in Sprague-Dawley rats to assess insulin sensitivity and hypoglycemia counterregulation, respectively. RESULTS In vitro, we demonstrate that R481 increased AMPK phosphorylation in GT1-7 and αTC1.9 cells. In Sprague-Dawley rats, R481 increased peak glucose levels during a glucose tolerance test, without altering insulin levels or glucose clearance. The effect of R481 to raise peak glucose levels was attenuated by allosteric brain permeable AMPK inhibitor SBI-0206965. This effect was also completely abolished by blockade of the autonomic nervous system using hexamethonium. During hypoglycemic clamp studies, R481 treated animals had a significantly lower glucose infusion rate compared to vehicle treated controls. Peak plasma glucagon levels were significantly higher in R481 treated rats with no change to plasma adrenaline levels. In vitro, R481 did not alter glucagon release from αTC1.9 cells, but increased glycolysis. Non brain permeable AMPK activator R419 enhanced AMPK activity in vitro in neuronal cells but did not alter glucose excursion in vivo. CONCLUSIONS These data demonstrate that peripheral administration of the brain permeable "metformin-like" AMPK activator R481 increases blood glucose by activation of the autonomic nervous system and amplifies the glucagon response to hypoglycemia in rats. Taken together, our data suggest that R481 amplifies the counterregulatory response to hypoglycemia by a central rather than a direct effect on the pancreatic α-cell. These data provide proof-of-concept that central AMPK could be a target for future drug development for prevention of hypoglycemia in diabetes.
Collapse
Affiliation(s)
- Ana M Cruz
- Institute of Biomedical and Clinical Sciences, College of Medicine and Health, University of Exeter, Exeter, United Kingdom
| | - Katie M Partridge
- Institute of Biomedical and Clinical Sciences, College of Medicine and Health, University of Exeter, Exeter, United Kingdom
| | - Yasaman Malekizadeh
- Institute of Biomedical and Clinical Sciences, College of Medicine and Health, University of Exeter, Exeter, United Kingdom
| | - Julia M Vlachaki Walker
- Institute of Biomedical and Clinical Sciences, College of Medicine and Health, University of Exeter, Exeter, United Kingdom
| | - Paul G Weightman Potter
- Institute of Biomedical and Clinical Sciences, College of Medicine and Health, University of Exeter, Exeter, United Kingdom
| | - Katherine R Pye
- Institute of Biomedical and Clinical Sciences, College of Medicine and Health, University of Exeter, Exeter, United Kingdom
| | - Simon J Shaw
- Rigel Pharmaceuticals Inc., South San Francisco, CA, United States
| | - Kate L J Ellacott
- Institute of Biomedical and Clinical Sciences, College of Medicine and Health, University of Exeter, Exeter, United Kingdom
| | - Craig Beall
- Institute of Biomedical and Clinical Sciences, College of Medicine and Health, University of Exeter, Exeter, United Kingdom
| |
Collapse
|
10
|
Deng W, Sun J, Chang ZG, Gou NN, Wu WY, Luo XL, Zhou JS, Yu HB, Ji H. Energy response and fatty acid metabolism in Onychostoma macrolepis exposed to low-temperature stress. J Therm Biol 2020; 94:102725. [PMID: 33292981 DOI: 10.1016/j.jtherbio.2020.102725] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 08/11/2020] [Accepted: 09/01/2020] [Indexed: 10/23/2022]
Abstract
Temperature is a key environmental factor, and understanding how its fluctuations affect physiological and metabolic processes is critical for fish. The present study characterizes the energy response and fatty acid metabolism in Onychostoma macrolepis exposed to low temperature (10 °C). The results demonstrated that cold stress remarkably disrupted the energy homeostasis of O. macrolepis, then the AMP-activated protein kinase (AMPK) could strategically mobilize carbohydrates and lipids. In particular, when the O. macrolepis were faced with cold stress, the lipolysis was stimulated along with the enhanced fatty acid β-oxidation for energy, while the fatty acid synthesis was supressed in the early stage. Additionally, the fatty acid composition analysis suggested that saturated fatty acid (SFA) might accumulate while monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA) in storage lipids (mainly containing non-polar lipid, NPL) could be utilized to supply energy during cold acclimation. Altogether, this study may provide some meritorious for understanding the cold-tolerant mechanism of fish in the viewpoint of energy balance combined with fatty acid metabolism, and thus to contribute to this species rearing in fish farms in the future.
Collapse
Affiliation(s)
- Wei Deng
- College of Animal Science and Technology, Northwest Agriculture and Forestry University, Yangling, 712100, China
| | - Jian Sun
- College of Animal Science and Technology, Northwest Agriculture and Forestry University, Yangling, 712100, China
| | - Zhi-Guang Chang
- College of Animal Science and Technology, Northwest Agriculture and Forestry University, Yangling, 712100, China
| | - Ni-Na Gou
- College of Animal Science and Technology, Northwest Agriculture and Forestry University, Yangling, 712100, China
| | - Wen-Yi Wu
- College of Animal Science and Technology, Northwest Agriculture and Forestry University, Yangling, 712100, China
| | - Xiao-Long Luo
- College of Animal Science and Technology, Northwest Agriculture and Forestry University, Yangling, 712100, China
| | - Ji-Shu Zhou
- College of Animal Science and Technology, Northwest Agriculture and Forestry University, Yangling, 712100, China
| | - Hai-Bo Yu
- College of Animal Science and Technology, Northwest Agriculture and Forestry University, Yangling, 712100, China.
| | - Hong Ji
- College of Animal Science and Technology, Northwest Agriculture and Forestry University, Yangling, 712100, China.
| |
Collapse
|
11
|
Lien YC, Won KJ, Simmons RA. Transcriptomic and Quantitative Proteomic Profiling Reveals Signaling Pathways Critical for Pancreatic Islet Maturation. Endocrinology 2020; 161:5923720. [PMID: 33053583 PMCID: PMC7668240 DOI: 10.1210/endocr/bqaa187] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Indexed: 02/07/2023]
Abstract
Pancreatic β-cell dysfunction and reduced insulin secretion play a key role in the pathogenesis of diabetes. Fetal and neonatal islets are functionally immature and have blunted glucose responsiveness and decreased insulin secretion in response to stimuli and are far more proliferative. However, the mechanisms underlying functional immaturity are not well understood. Pancreatic islets are composed of a mixture of different cell types, and the microenvironment of islets and interactions between these cell types are critical for β-cell development and maturation. RNA sequencing and quantitative proteomic data from intact islets isolated from fetal (embryonic day 19) and 2-week-old Sprague-Dawley rats were integrated to compare their gene and protein expression profiles. Ingenuity Pathway Analysis (IPA) was also applied to elucidate pathways and upstream regulators modulating functional maturation of islets. By integrating transcriptome and proteomic data, 917 differentially expressed genes/proteins were identified with a false discovery rate of less than 0.05. A total of 411 and 506 of them were upregulated and downregulated in the 2-week-old islets, respectively. IPA revealed novel critical pathways associated with functional maturation of islets, such as AMPK (adenosine monophosphate-activated protein kinase) and aryl hydrocarbon receptor signaling, as well as the importance of lipid homeostasis/signaling and neuronal function. Furthermore, we also identified many proteins enriched either in fetal or 2-week-old islets related to extracellular matrix and cell communication, suggesting that these pathways play critical roles in islet maturation. Our present study identified novel pathways for mature islet function in addition to confirming previously reported mechanisms, and provided new mechanistic insights for future research on diabetes prevention and treatment.
Collapse
Affiliation(s)
- Yu-Chin Lien
- Center for Research on Reproduction and Women’s Health, Perelman School of Medicine, the University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Division of Neonatology, Department of Pediatrics, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Kyoung-Jae Won
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Stem Cell Biology (DanStem), Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Rebecca A Simmons
- Center for Research on Reproduction and Women’s Health, Perelman School of Medicine, the University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Division of Neonatology, Department of Pediatrics, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Correspondence: Rebecca A. Simmons, MD, Center for Research on Reproduction and Women’s Health, Perelman School of Medicine, the University of Pennsylvania, BRB II/III, 13th Fl, Rm 1308, 421 Curie Blvd, Philadelphia, PA 19104, USA. E-mail:
| |
Collapse
|
12
|
Georgiadou E, Haythorne E, Dickerson MT, Lopez-Noriega L, Pullen TJ, da Silva Xavier G, Davis SPX, Martinez-Sanchez A, Semplici F, Rizzuto R, McGinty JA, French PM, Cane MC, Jacobson DA, Leclerc I, Rutter GA. The pore-forming subunit MCU of the mitochondrial Ca 2+ uniporter is required for normal glucose-stimulated insulin secretion in vitro and in vivo in mice. Diabetologia 2020; 63:1368-1381. [PMID: 32350566 PMCID: PMC7286857 DOI: 10.1007/s00125-020-05148-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Accepted: 02/27/2020] [Indexed: 12/28/2022]
Abstract
AIMS/HYPOTHESIS Mitochondrial oxidative metabolism is central to glucose-stimulated insulin secretion (GSIS). Whether Ca2+ uptake into pancreatic beta cell mitochondria potentiates or antagonises this process is still a matter of debate. Although the mitochondrial Ca2+ importer (MCU) complex is thought to represent the main route for Ca2+ transport across the inner mitochondrial membrane, its role in beta cells has not previously been examined in vivo. METHODS Here, we inactivated the pore-forming subunit of the MCU, encoded by Mcu, selectively in mouse beta cells using Ins1Cre-mediated recombination. Whole or dissociated pancreatic islets were isolated and used for live beta cell fluorescence imaging of cytosolic or mitochondrial Ca2+ concentration and ATP production in response to increasing glucose concentrations. Electrophysiological recordings were also performed on whole islets. Serum and blood samples were collected to examine oral and i.p. glucose tolerance. RESULTS Glucose-stimulated mitochondrial Ca2+ accumulation (p< 0.05), ATP production (p< 0.05) and insulin secretion (p< 0.01) were strongly inhibited in beta cell-specific Mcu-null (βMcu-KO) animals, in vitro, as compared with wild-type (WT) mice. Interestingly, cytosolic Ca2+ concentrations increased (p< 0.001), whereas mitochondrial membrane depolarisation improved in βMcu-KO animals. βMcu-KO mice displayed impaired in vivo insulin secretion at 5 min (p< 0.001) but not 15 min post-i.p. injection of glucose, whilst the opposite phenomenon was observed following an oral gavage at 5 min. Unexpectedly, glucose tolerance was improved (p< 0.05) in young βMcu-KO (<12 weeks), but not in older animals vs WT mice. CONCLUSIONS/INTERPRETATION MCU is crucial for mitochondrial Ca2+ uptake in pancreatic beta cells and is required for normal GSIS. The apparent compensatory mechanisms that maintain glucose tolerance in βMcu-KO mice remain to be established.
Collapse
Affiliation(s)
- Eleni Georgiadou
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Elizabeth Haythorne
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Matthew T Dickerson
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, USA
| | - Livia Lopez-Noriega
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Timothy J Pullen
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Gabriela da Silva Xavier
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Samuel P X Davis
- Photonics Group, Department of Physics, Imperial College London, London, UK
| | - Aida Martinez-Sanchez
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Francesca Semplici
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Rosario Rizzuto
- Department of Biomedical Sciences, University of Padova, Padua, Italy
| | - James A McGinty
- Photonics Group, Department of Physics, Imperial College London, London, UK
| | - Paul M French
- Photonics Group, Department of Physics, Imperial College London, London, UK
| | - Matthew C Cane
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - David A Jacobson
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, USA
| | - Isabelle Leclerc
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Guy A Rutter
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, Du Cane Road, London, W12 0NN, UK.
| |
Collapse
|
13
|
Xu W, Zhao T, Xiao H. The Implication of Oxidative Stress and AMPK-Nrf2 Antioxidative Signaling in Pneumonia Pathogenesis. Front Endocrinol (Lausanne) 2020; 11:400. [PMID: 32625169 PMCID: PMC7311749 DOI: 10.3389/fendo.2020.00400] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Accepted: 05/18/2020] [Indexed: 02/05/2023] Open
Abstract
It is widely recognized that chemical, physical, and biological factors can singly or synergistically evoke the excessive production of oxidative stress in pulmonary tissue that followed by pulmonary lesions and pneumonia. In addition, metabolic and endocrine disorder-induced diseases such as diabetes and obesity often expressed higher susceptibility to pulmonary infections, and presented severe symptoms which increasing the mortality rate. Therefore, the connection between the lesion of the lungs and the metabolic/endocrine disorders is an interesting and essential issue to be addressed. Studies have noticed a similar pathological feature in both infectious pneumonia and metabolic disease-intercurrent pulmonary lesions, that is, from the view of molecular pathology, the accumulation of excessive reactive oxygen species (ROS) in pulmonary tissue accompanying with activated pro-inflammatory signals. Meanwhile, Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) and nuclear factor erythroid-2-related factor 2 (Nrf2) signaling plays important role in metabolic/endocrine homeostasis and infection response, and it's closely associated with the anti-oxidative capacity of the body. For this reason, this review will start from the summary upon the implication of ROS accumulation, and to discuss how AMPK-Nrf2 signaling contributes to maintaining the metabolic/endocrine homeostasis and attenuates the susceptibility of pulmonary infections.
Collapse
Affiliation(s)
| | | | - Hengyi Xiao
- Lab for Aging Research, State Key Laboratory of Biotherapy, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
| |
Collapse
|
14
|
Uddin SJ, Afroz M, Zihad SMNK, Rahman MS, Akter S, Khan IN, Al-Rabbi SMS, Rouf R, Islam MT, Shilpi JA, Nahar L, Tiralongo E, Sarker SD. A Systematic Review on Anti-diabetic and Cardioprotective Potential of Gallic Acid: A Widespread Dietary Phytoconstituent. FOOD REVIEWS INTERNATIONAL 2020. [DOI: 10.1080/87559129.2020.1734609] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Shaikh Jamal Uddin
- Department for Management of Science and Technology Development, Ton Duc Thang University, Ho Chi Minh City, Vietnam
- Faculty of Pharmacy, Ton Duc Thang University, Ho Chi Minh City, Vietnam
| | - Mohasana Afroz
- Pharmacy Discipline, Life Science School, Khulna University, Khulna, Bangladesh
| | | | - Md. Shamim Rahman
- Biotechnology and Genetic Engineering Discipline, Life Science School, Khulna University, Khulna, Bangladesh
| | - Sanzida Akter
- Pharmacy Discipline, Life Science School, Khulna University, Khulna, Bangladesh
| | - Ishaq N. Khan
- PK-Neurooncology Research Group, Institute of Basic Medical Sciences, Khyber Medical University, Peshawar, 25000, Pakistan
| | | | - Razina Rouf
- Department of Pharmacy, Faculty of Life Science, Bangabandhu Sheikh Mujibur Rahman Science & Technology University, Gopalganj, Bangladesh
| | - Muhammad Torequl Islam
- Department of Pharmacy, Faculty of Life Science, Bangabandhu Sheikh Mujibur Rahman Science & Technology University, Gopalganj, Bangladesh
| | - Jamil A. Shilpi
- Pharmacy Discipline, Life Science School, Khulna University, Khulna, Bangladesh
| | - Lutfun Nahar
- Centre for Natural Products Discovery, School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, James Parsons Building, Byrom Street, LiverpoolL3 3AF, UK
| | - Evelin Tiralongo
- School of Pharmacy and Pharmacology & Menzies Health Institute Queensland, Griffith University, Southport, Qld, Australia
| | - Satyajit D. Sarker
- Centre for Natural Products Discovery, School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, James Parsons Building, Byrom Street, LiverpoolL3 3AF, UK
| |
Collapse
|
15
|
Prentki M, Corkey BE, Madiraju SRM. Lipid-associated metabolic signalling networks in pancreatic beta cell function. Diabetologia 2020; 63:10-20. [PMID: 31423551 DOI: 10.1007/s00125-019-04976-w] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 05/29/2019] [Indexed: 01/01/2023]
Abstract
Significant advances have been made in deciphering the mechanisms underlying fuel-stimulated insulin secretion by pancreatic beta cells. The contribution of the triggering/ATP-sensitive potassium (KATP)-dependent Ca2+ signalling and KATP-independent amplification pathways, that include anaplerosis and lipid signalling of glucose-stimulated insulin secretion (GSIS), are well established. A proposed model included a key role for a metabolic partitioning 'switch', the acetyl-CoA carboxylase (ACC)/malonyl-CoA/carnitine palmitoyltransferase-1 (CPT-1) axis, in beta cell glucose and fatty acid signalling for insulin secretion. This model has gained overwhelming support from a number of studies in recent years and is now refined through its link to the glycerolipid/NEFA cycle that provides lipid signals through its lipolysis arm. Furthermore, acetyl-CoA carboxylase may also control beta cell growth. Here we review the evidence supporting a role for the ACC/malonyl-CoA/CPT-1 axis in the control of GSIS and its particular importance under conditions of elevated fatty acids (e.g. fasting, excess nutrients, hyperlipidaemia and diabetes). We also document how it is linked to a more global lipid signalling system that includes the glycerolipid/NEFA cycle.
Collapse
Affiliation(s)
- Marc Prentki
- Department of Nutrition, University of Montreal, Montréal, QC, Canada.
- Department of Biochemistry and Molecular Medicine, University of Montreal, Montréal, QC, Canada.
- Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Viger Tour, 900 rue Saint Denis, Room R08-412, Montréal, QC, H2X 0A9, Canada.
| | - Barbara E Corkey
- Evans Department of Medicine, Obesity Research Center, Boston University School of Medicine, Boston, MA, USA
| | - S R Murthy Madiraju
- Department of Nutrition, University of Montreal, Montréal, QC, Canada
- Department of Biochemistry and Molecular Medicine, University of Montreal, Montréal, QC, Canada
- Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Viger Tour, 900 rue Saint Denis, Room R08-412, Montréal, QC, H2X 0A9, Canada
| |
Collapse
|
16
|
Davis SPX, Kumar S, Alexandrov Y, Bhargava A, da Silva Xavier G, Rutter GA, Frankel P, Sahai E, Flaxman S, French PMW, McGinty J. Convolutional neural networks for reconstruction of undersampled optical projection tomography data applied to in vivo imaging of zebrafish. JOURNAL OF BIOPHOTONICS 2019; 12:e201900128. [PMID: 31386281 PMCID: PMC7065643 DOI: 10.1002/jbio.201900128] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 06/27/2019] [Accepted: 08/04/2019] [Indexed: 06/10/2023]
Abstract
Optical projection tomography (OPT) is a 3D mesoscopic imaging modality that can utilize absorption or fluorescence contrast. 3D images can be rapidly reconstructed from tomographic data sets sampled with sufficient numbers of projection angles using the Radon transform, as is typically implemented with optically cleared samples of the mm-to-cm scale. For in vivo imaging, considerations of phototoxicity and the need to maintain animals under anesthesia typically preclude the acquisition of OPT data at a sufficient number of angles to avoid artifacts in the reconstructed images. For sparse samples, this can be addressed with iterative algorithms to reconstruct 3D images from undersampled OPT data, but the data processing times present a significant challenge for studies imaging multiple animals. We show here that convolutional neural networks (CNN) can be used in place of iterative algorithms to remove artifacts-reducing processing time for an undersampled in vivo zebrafish dataset from 77 to 15 minutes. We also show that using CNN produces reconstructions of equivalent quality to compressed sensing with 40% fewer projections. We further show that diverse training data classes, for example, ex vivo mouse tissue data, can be used for CNN-based reconstructions of OPT data of other species including live zebrafish.
Collapse
Affiliation(s)
| | - Sunil Kumar
- Department of PhysicsImperial College LondonLondonUK
- The Francis Crick InstituteLondonUK
| | - Yuriy Alexandrov
- Department of PhysicsImperial College LondonLondonUK
- The Francis Crick InstituteLondonUK
| | | | - Gabriela da Silva Xavier
- Department of MedicineImperial College LondonLondonUK
- Institute of Metabolism and Systems ResearchUniversity of BirminghamBirminghamUK
| | - Guy A. Rutter
- Department of MedicineImperial College LondonLondonUK
| | - Paul Frankel
- Division of MedicineUniversity College LondonLondonUK
| | | | - Seth Flaxman
- Department of Mathematics and Data Science InstituteImperial College LondonLondonUK
| | - Paul M. W. French
- Department of PhysicsImperial College LondonLondonUK
- The Francis Crick InstituteLondonUK
| | - James McGinty
- Department of PhysicsImperial College LondonLondonUK
- The Francis Crick InstituteLondonUK
| |
Collapse
|
17
|
Kubi JA, Chen ACH, Fong SW, Lai KP, Wong CKC, Yeung WSB, Lee KF, Lee YL. Effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on the differentiation of embryonic stem cells towards pancreatic lineage and pancreatic beta cell function. ENVIRONMENT INTERNATIONAL 2019; 130:104885. [PMID: 31195220 DOI: 10.1016/j.envint.2019.05.079] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 05/21/2019] [Accepted: 05/31/2019] [Indexed: 06/09/2023]
Abstract
Animal and epidemiological studies demonstrated association of persistent exposure of TCDD, an endocrine disrupting chemical, to susceptibility of type 2 diabetes (T2D). High doses of TCDD were commonly employed in experimental animals to illustrate its diabetogenic effects. Data linking the epigenetic effects of low doses of TCDD on embryonic cells to T2D susceptibility risks is very limited. To address whether low dose exposure to TCDD would affect pancreatic development, hESCs pretreated with TCDD at concentrations similar to human exposure were differentiated towards pancreatic lineage cells, and their global DNA methylation patterns were determined. Our results showed that TCDD-treated hESCs had impaired pancreatic lineage differentiation potentials and altered global DNA methylation patterns. Four of the hypermethylated genes (PRKAG1, CAPN10, HNF-1B and MAFA) were validated by DNA bisulfite sequencing. PRKAG1, a regulator in the AMPK signaling pathway critical for insulin secretion, was selected for further functional study in the rat insulinoma cell line, INS-1E cells. TCDD treatment induced PRKAG1 hypermethylation in hESCs, and the hypermethylation was maintained after pancreatic progenitor cells differentiation. Transient Prkag1 knockdown in the INS-1E cells elevated glucose stimulated insulin secretions (GSIS), possibly through mTOR signaling pathway. The current study suggested that early embryonic exposure to TCDD might alter pancreatogenesis, increasing the risk of T2D.
Collapse
Affiliation(s)
- John A Kubi
- Department of Obstetrics and Gynaecology, The University of Hong Kong, Hong Kong, China
| | - Andy C H Chen
- Department of Obstetrics and Gynaecology, The University of Hong Kong, Hong Kong, China; Shenzhen Key Laboratory of Fertility Regulation, The University of Hong Kong Shenzhen Hospital, Shenzhen, China
| | - Sze Wan Fong
- Department of Obstetrics and Gynaecology, The University of Hong Kong, Hong Kong, China
| | - Keng Po Lai
- Department of Chemistry, City University of Hong Kong, Hong Kong, China
| | - Chris K C Wong
- Croucher Institute for Environmental Sciences, Department of Biology, Hong Kong Baptist University, Hong Kong, China
| | - William S B Yeung
- Department of Obstetrics and Gynaecology, The University of Hong Kong, Hong Kong, China; Shenzhen Key Laboratory of Fertility Regulation, The University of Hong Kong Shenzhen Hospital, Shenzhen, China
| | - Kai Fai Lee
- Department of Obstetrics and Gynaecology, The University of Hong Kong, Hong Kong, China; Shenzhen Key Laboratory of Fertility Regulation, The University of Hong Kong Shenzhen Hospital, Shenzhen, China.
| | - Yin Lau Lee
- Department of Obstetrics and Gynaecology, The University of Hong Kong, Hong Kong, China; Shenzhen Key Laboratory of Fertility Regulation, The University of Hong Kong Shenzhen Hospital, Shenzhen, China.
| |
Collapse
|
18
|
Jaafar R, Tran S, Shah AN, Sun G, Valdearcos M, Marchetti P, Masini M, Swisa A, Giacometti S, Bernal-Mizrachi E, Matveyenko A, Hebrok M, Dor Y, Rutter GA, Koliwad SK, Bhushan A. mTORC1 to AMPK switching underlies β-cell metabolic plasticity during maturation and diabetes. J Clin Invest 2019; 129:4124-4137. [PMID: 31265435 PMCID: PMC6763225 DOI: 10.1172/jci127021] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 06/24/2019] [Indexed: 12/28/2022] Open
Abstract
Pancreatic beta cells (β-cells) differentiate during fetal life, but only postnatally acquire the capacity for glucose-stimulated insulin secretion (GSIS). How this happens is not clear. In exploring what molecular mechanisms drive the maturation of β-cell function, we found that the control of cellular signaling in β-cells fundamentally switched from the nutrient sensor target of rapamycin (mTORC1) to the energy sensor 5'-adenosine monophosphate-activated protein kinase (AMPK), and that this was critical for functional maturation. Moreover, AMPK was activated by the dietary transition taking place during weaning, and this in turn inhibited mTORC1 activity to drive the adult β-cell phenotype. While forcing constitutive mTORC1 signaling in adult β-cells relegated them to a functionally immature phenotype with characteristic transcriptional and metabolic profiles, engineering the switch from mTORC1 to AMPK signaling was sufficient to promote β-cell mitochondrial biogenesis, a shift to oxidative metabolism, and functional maturation. We also found that type 2 diabetes, a condition marked by both mitochondrial degeneration and dysregulated GSIS, was associated with a remarkable reversion of the normal AMPK-dependent adult β-cell signature to a more neonatal one characterized by mTORC1 activation. Manipulating the way in which cellular nutrient signaling pathways regulate β-cell metabolism may thus offer new targets to improve β-cell function in diabetes.
Collapse
Affiliation(s)
- Rami Jaafar
- The Diabetes Center, UCSF, San Francisco, California, USA
| | - Stella Tran
- The Diabetes Center, UCSF, San Francisco, California, USA
| | - Ajit N. Shah
- The Diabetes Center, UCSF, San Francisco, California, USA
| | - Gao Sun
- Section of Cell Biology and Functional Genomics, Department of Medicine, Imperial College London, Hammersmith Hospital London, United Kingdom
| | | | - Piero Marchetti
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Matilde Masini
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Avital Swisa
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | | | - Ernesto Bernal-Mizrachi
- Division of Endocrinology, Diabetes and Metabolism, University of Miami, Miller School of Medicine, Miami, Florida, USA
| | - Aleksey Matveyenko
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
| | | | - Yuval Dor
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Guy A. Rutter
- Section of Cell Biology and Functional Genomics, Department of Medicine, Imperial College London, Hammersmith Hospital London, United Kingdom
| | | | - Anil Bhushan
- The Diabetes Center, UCSF, San Francisco, California, USA
| |
Collapse
|
19
|
Qian L, Shi H, Ding M. Comparative analysis of gene expression profiles in children with type 1 diabetes mellitus. Mol Med Rep 2019; 19:3989-4000. [PMID: 30942443 PMCID: PMC6472094 DOI: 10.3892/mmr.2019.10099] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 06/22/2018] [Indexed: 01/07/2023] Open
Abstract
Type 1 diabetes (T1D) is an autoimmune disease that is typically diagnosed in children. The aim of the present study was to identify potential genes involved in the pathogenesis of childhood T1D. Two datasets of mRNA expression in children with T1D were obtained from the Gene Expression Omnibus (GEO). Differentially expressed genes (DEGs) in children with T1D were identified. Functional analysis was performed and a protein‑protein interaction (PPI) network was constructed, as was a transcription factor (TF)‑target network. The expression of selected DEGs was further assessed using reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) analysis. Electronic validation and diagnostic value analysis of the identified DEGs [cytokine inducible SH2 containing protein (CISH), SR‑related CTD associated factor 11 (SCAF11), estrogen receptor 1 (ESR1), Rho GTPase activating protein 25 (ARHGAP25), major histocompatibility complex, class II, DR β4 (HLA‑DRB4) and interleukin 23 subunit α (IL23A)] was performed in the GEO dataset. Compared with the normal control group, a total of 1,467 DEGs with P<0.05 were identified in children with T1D. CISH and SCAF11 were determined to be the most up‑ and downregulated genes, respectively. Heterogeneous nuclear ribonucleoprotein D (HNRNPD; degree=33), protein kinase AMP‑activated catalytic subunit α1 (PRKAA1; degree=11), integrin subunit α4 (ITGA4; degree=8) and ESR1 (degree=8) were identified in the PPI network as high‑degree genes. ARHGAP25 (degree=12), HNRNPD (degree=10), HLA‑DRB4 (degree=10) and IL23A (degree=9) were high‑degree genes identified in the TF‑target network. RT‑qPCR revealed that the expression of HNRNPD, PRKAA1, ITGA4 and transporter 2, ATP binding cassette subfamily B member was consistent with the results of the integrated analysis. Furthermore, the results of the electronic validation were consistent with the bioinformatics analysis. SCAF11, CISH and ARHGAP25 were identified to possess value as potential diagnostic markers for children with T1D. In conclusion, identifying DEGs in children with T1D may contribute to our understanding of its pathogenesis, and such DEGs may be used as diagnostic biomarkers for children with T1D.
Collapse
Affiliation(s)
- Liwei Qian
- Department of Pediatrics, The Second People's Hospital of Liaocheng, Liaocheng, Shandong 252000, P.R. China
| | - Honglei Shi
- Department of Pediatrics, The Second People's Hospital of Liaocheng, Liaocheng, Shandong 252000, P.R. China
| | - Meili Ding
- Department of Pediatrics, Shandong Jining No. 1 People's Hospital, Jining, Shandong 272011, P.R. China
| |
Collapse
|
20
|
Jin S, Bian C, Jiang S, Sun S, Xu L, Xiong Y, Qiao H, Zhang W, You X, Li J, Gong Y, Ma B, Shi Q, Fu H. Identification of Candidate Genes for the Plateau Adaptation of a Tibetan Amphipod, Gammarus lacustris, Through Integration of Genome and Transcriptome Sequencing. Front Genet 2019; 10:53. [PMID: 30804987 PMCID: PMC6378286 DOI: 10.3389/fgene.2019.00053] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 01/22/2019] [Indexed: 01/16/2023] Open
Abstract
The amphipod Gammarus lacustris has been distributing in the Tibetan region with well-known uplifts of the Tibetan plateau. It is hence considered as a good model for investigating stress adaptations of the plateau. Here, we sequenced the whole-genome and full-length transcriptome of G. lacustris, and compared the transcriptome results with its counterpart Gammarus pisinnus from a nearby plain. Our main goal was to provide a genomic resource for investigation of genetic mechanisms, by which G. lacustris adapted to living on the plateau. The final draft genome assembly of G. lacustris was 5.07 gigabases (Gb), and it contained 443,304 scaffolds (>2 kb) with an N50 of 2,578 bp. A total of 8,858 unigenes were predicted in the full-length transcriptome of G. lacustris, with an average gene length of 1,811 bp. Compared with the G. pisinnus transcriptome, 2,672 differentially expressed genes (DEGs) were up-regulated and 2,881 DEGs were down-regulated in the G. lacustris transcriptome. Along with these critical DEGs, several enriched metabolic pathways, such as oxidative phosphorylation, ribosome, cell energy homeostasis, glycolysis and gluconeogenesis, were predicted to play essential roles in the plateau adaptation. In summary, the present study provides a genomic basis for understanding the plateau adaption of G. lacustris, which lays a fundamental basis for further biological and ecological studies on other resident aquatic species in the Tibetan plateau.
Collapse
Affiliation(s)
- Shubo Jin
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
| | - Chao Bian
- BGI Research Center for Aquatic Genomics, Chinese Academy of Fishery Sciences, Shenzhen, China
- Shenzhen Key Lab of Marine Genomics, Guangdong Provincial Key Lab of Molecular Breeding in Marine Economic Animals, BGI, Shenzhen, China
- Centre of Reproduction, Development and Aging, Faculty of Health Sciences, University of Macau, Taipa, China
| | - Sufei Jiang
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
| | - Shengming Sun
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
| | - Lei Xu
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, China
| | - Yiwei Xiong
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
| | - Hui Qiao
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
| | - Wenyi Zhang
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
| | - Xinxin You
- BGI Research Center for Aquatic Genomics, Chinese Academy of Fishery Sciences, Shenzhen, China
- Shenzhen Key Lab of Marine Genomics, Guangdong Provincial Key Lab of Molecular Breeding in Marine Economic Animals, BGI, Shenzhen, China
| | - Jia Li
- BGI Research Center for Aquatic Genomics, Chinese Academy of Fishery Sciences, Shenzhen, China
- Shenzhen Key Lab of Marine Genomics, Guangdong Provincial Key Lab of Molecular Breeding in Marine Economic Animals, BGI, Shenzhen, China
| | - Yongsheng Gong
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
| | - Bo Ma
- Heilongjiang River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Haebin, China
| | - Qiong Shi
- BGI Research Center for Aquatic Genomics, Chinese Academy of Fishery Sciences, Shenzhen, China
- Shenzhen Key Lab of Marine Genomics, Guangdong Provincial Key Lab of Molecular Breeding in Marine Economic Animals, BGI, Shenzhen, China
| | - Hongtuo Fu
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
| |
Collapse
|
21
|
Abstract
The role of the energy sensor AMPK-activated protein kinase (AMPK) in the insulin-secreting β-cell remains unclear and a subject of intense research. With this chapter, we aim to provide a detailed description of the methods that our group routinely applies to the study of AMPK function in mouse and human pancreatic islets. Thus, we provide detailed protocols to isolate and/or culture mouse and human islets, to modulate and measure AMPK activity in isolated islets, and to evaluate its impact on islet function.
Collapse
|
22
|
Ballak DB, Li S, Cavalli G, Stahl JL, Tengesdal IW, van Diepen JA, Klück V, Swartzwelter B, Azam T, Tack CJ, Stienstra R, Mandrup-Poulsen T, Seals DR, Dinarello CA. Interleukin-37 treatment of mice with metabolic syndrome improves insulin sensitivity and reduces pro-inflammatory cytokine production in adipose tissue. J Biol Chem 2018; 293:14224-14236. [PMID: 30006351 PMCID: PMC6139546 DOI: 10.1074/jbc.ra118.003698] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 07/06/2018] [Indexed: 12/22/2022] Open
Abstract
Obesity and the metabolic syndrome are characterized by chronic, low-grade inflammation mainly originating from expanding adipose tissue and resulting in inhibition of insulin signaling and disruption of glycemic control. Transgenic mice expressing human interleukin 37 (IL-37), an anti-inflammatory cytokine of the IL-1 family, are protected against metabolic syndrome when fed a high-fat diet (HFD) containing 45% fat. Here, we examined whether treatment with recombinant IL-37 ameliorates established insulin resistance and obesity-induced inflammation. WT mice were fed a HFD for 22 weeks and then treated daily with IL-37 (1 μg/mouse) during the last 2 weeks. Compared with vehicle only-treated mice, IL-37-treated mice exhibited reduced insulin in the plasma and had significant improvements in glucose tolerance and in insulin content of the islets. The IL-37 treatment also increased the levels of circulating IL-1 receptor antagonist. Cultured adipose tissues revealed that IL-37 treatment significantly decreases spontaneous secretions of IL-1β, tumor necrosis factor α (TNFα), and CXC motif chemokine ligand 1 (CXCL-1). We also fed mice a 60% fat diet with concomitant daily IL-37 for 2 weeks and observed decreased secretion of IL-1β, TNFα, and IL-6 and reduced intracellular levels of IL-1α in the liver and adipose tissue, along with improved plasma glucose clearance. Compared with vehicle treatment, these IL-37-treated mice had no apparent weight gain. In human adipose tissue cultures, the presence of 50 pm IL-37 reduced spontaneous release of TNFα and 50% of lipopolysaccharide-induced TNFα. These findings indicate that IL-37's anti-inflammatory effects can ameliorate established metabolic disturbances during obesity.
Collapse
Affiliation(s)
- Dov B. Ballak
- From the Department of Medicine, University of Colorado Denver, Aurora, Colorado 80045, ,the Department of Integrative Physiology, University of Colorado Boulder, Boulder, Colorado 80309
| | - Suzhao Li
- From the Department of Medicine, University of Colorado Denver, Aurora, Colorado 80045
| | - Giulio Cavalli
- From the Department of Medicine, University of Colorado Denver, Aurora, Colorado 80045
| | - Jonathan L. Stahl
- the Department of Biomedical Sciences, University of Copenhagen, 1165 Copenhagen, Denmark
| | - Isak W. Tengesdal
- From the Department of Medicine, University of Colorado Denver, Aurora, Colorado 80045
| | - Janna A. van Diepen
- the Department of Medicine, Radboud University Medical Center, 6525 Nijmegen, The Netherlands, and
| | - Viola Klück
- From the Department of Medicine, University of Colorado Denver, Aurora, Colorado 80045
| | - Benjamin Swartzwelter
- From the Department of Medicine, University of Colorado Denver, Aurora, Colorado 80045
| | - Tania Azam
- From the Department of Medicine, University of Colorado Denver, Aurora, Colorado 80045
| | - Cees J. Tack
- the Department of Medicine, Radboud University Medical Center, 6525 Nijmegen, The Netherlands, and
| | - Rinke Stienstra
- the Department of Medicine, Radboud University Medical Center, 6525 Nijmegen, The Netherlands, and ,the Division of Human Nutrition, Wageningen University, 6525 Wageningen, The Netherlands
| | - Thomas Mandrup-Poulsen
- the Department of Biomedical Sciences, University of Copenhagen, 1165 Copenhagen, Denmark
| | - Douglas R. Seals
- the Department of Integrative Physiology, University of Colorado Boulder, Boulder, Colorado 80309
| | - Charles A. Dinarello
- From the Department of Medicine, University of Colorado Denver, Aurora, Colorado 80045, ,the Department of Medicine, Radboud University Medical Center, 6525 Nijmegen, The Netherlands, and , To whom correspondence should be addressed:
Dept. of Medicine, University of Colorado Denver, Aurora, Colorado 80045. Tel.:
303-724-6174; Fax:
303-724-6178; E-mail:
| |
Collapse
|
23
|
Mészáros G, Pasquier A, Vivot K, Goginashvili A, Ricci R. Lysosomes in nutrient signalling: A focus on pancreatic β-cells. Diabetes Obes Metab 2018; 20 Suppl 2:104-115. [PMID: 30230186 DOI: 10.1111/dom.13389] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 05/24/2018] [Accepted: 05/28/2018] [Indexed: 01/12/2023]
Abstract
Regulated insulin secretion from pancreatic β-cells is a major process maintaining glucose homeostasis in mammals. Enhancing insulin release in response to chronic nutrient overload and obesity-related insulin resistance (pre-diabetes) requires several adaptive cellular mechanisms maintaining β-cell health under such stresses. Once these mechanisms are overwhelmed, β-cell failure occurs leading to full-blown Type 2 Diabetes (T2D). Nutrient-dependent macroautophagy represents one such adaptive mechanism in β-cells. While macroautophagy levels are high and protective in β-cells in pre-diabetes, they decrease at later stages contributing to β-cell failure. However, mechanisms compromising macroautophagy in β-cells remain poorly understood. In this review, we discuss how recently discovered signalling cascades that emanate from the limiting membrane of lysosomes contribute to changes in macroautophagy flux in physiology and disease. In particular, these mechanisms are put into context with β-cell function highlighting most recently described links between nutrient-dependent lysosomal signalling pathways and insulin secretion. Understanding these mechanisms in response to metabolic stress might pave the way for development of more tailored treatment strategies aimed at preserving β-cell health.
Collapse
Affiliation(s)
- Gergő Mészáros
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
- Centre National de la Recherche Scientifique, UMR7104, Illkirch, France
- Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France
- Université de Strasbourg, Strasbourg, France
- Laboratoire de Biochimie et de Biologie Moléculaire, Nouvel Hôpital Civil, Strasbourg, France
| | - Adrien Pasquier
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
- Centre National de la Recherche Scientifique, UMR7104, Illkirch, France
- Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France
- Université de Strasbourg, Strasbourg, France
| | - Kevin Vivot
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
- Centre National de la Recherche Scientifique, UMR7104, Illkirch, France
- Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France
- Université de Strasbourg, Strasbourg, France
| | - Alexander Goginashvili
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
- Centre National de la Recherche Scientifique, UMR7104, Illkirch, France
- Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France
- Université de Strasbourg, Strasbourg, France
- Ludwig Institute for Cancer Research, Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California
| | - Romeo Ricci
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
- Centre National de la Recherche Scientifique, UMR7104, Illkirch, France
- Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France
- Université de Strasbourg, Strasbourg, France
- Laboratoire de Biochimie et de Biologie Moléculaire, Nouvel Hôpital Civil, Strasbourg, France
| |
Collapse
|
24
|
Steneberg P, Lindahl E, Dahl U, Lidh E, Straseviciene J, Backlund F, Kjellkvist E, Berggren E, Lundberg I, Bergqvist I, Ericsson M, Eriksson B, Linde K, Westman J, Edlund T, Edlund H. PAN-AMPK activator O304 improves glucose homeostasis and microvascular perfusion in mice and type 2 diabetes patients. JCI Insight 2018; 3:99114. [PMID: 29925691 DOI: 10.1172/jci.insight.99114] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 05/17/2018] [Indexed: 12/20/2022] Open
Abstract
AMPK activated protein kinase (AMPK), a master regulator of energy homeostasis, is activated in response to an energy shortage imposed by physical activity and caloric restriction. We here report on the identification of PAN-AMPK activator O304, which - in diet-induced obese mice - increased glucose uptake in skeletal muscle, reduced β cell stress, and promoted β cell rest. Accordingly, O304 reduced fasting plasma glucose levels and homeostasis model assessment of insulin resistance (HOMA-IR) in a proof-of-concept phase IIa clinical trial in type 2 diabetes (T2D) patients on Metformin. T2D is associated with devastating micro- and macrovascular complications, and O304 improved peripheral microvascular perfusion and reduced blood pressure both in animals and T2D patients. Moreover, like exercise, O304 activated AMPK in the heart, increased cardiac glucose uptake, reduced cardiac glycogen levels, and improved left ventricular stroke volume in mice, but it did not increase heart weight in mice or rats. Thus, O304 exhibits a great potential as a novel drug to treat T2D and associated cardiovascular complications.
Collapse
Affiliation(s)
- Pär Steneberg
- Umeå Centre for Molecular Medicine, Umeå University, SE-901 87 Umeå, Sweden
| | - Emma Lindahl
- Umeå Centre for Molecular Medicine, Umeå University, SE-901 87 Umeå, Sweden
| | - Ulf Dahl
- Umeå Centre for Molecular Medicine, Umeå University, SE-901 87 Umeå, Sweden
| | - Emmelie Lidh
- Umeå Centre for Molecular Medicine, Umeå University, SE-901 87 Umeå, Sweden
| | | | - Fredrik Backlund
- Umeå Centre for Molecular Medicine, Umeå University, SE-901 87 Umeå, Sweden
| | | | - Eva Berggren
- Betagenon AB, Tvistevägen 48, SE-907 36 Umeå, Sweden
| | | | | | - Madelene Ericsson
- Department of Medical Biosciences, Umeå University, SE-901 87 Umeå, Sweden
| | | | - Kajsa Linde
- Betagenon AB, Tvistevägen 48, SE-907 36 Umeå, Sweden
| | - Jacob Westman
- Medchemcon AB, Jonsund Blomsberg 109, SE-744 97 Järlåsa, Sweden
| | - Thomas Edlund
- Umeå Centre for Molecular Medicine, Umeå University, SE-901 87 Umeå, Sweden.,Betagenon AB, Tvistevägen 48, SE-907 36 Umeå, Sweden
| | - Helena Edlund
- Umeå Centre for Molecular Medicine, Umeå University, SE-901 87 Umeå, Sweden
| |
Collapse
|
25
|
Rourke JL, Hu Q, Screaton RA. AMPK and Friends: Central Regulators of β Cell Biology. Trends Endocrinol Metab 2018; 29:111-122. [PMID: 29289437 DOI: 10.1016/j.tem.2017.11.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 11/20/2017] [Accepted: 11/29/2017] [Indexed: 02/08/2023]
Abstract
If left unchecked, prediabetic hyperglycemia can progress to diabetes and often life-threatening attendant secondary complications. Central to the process of glucose homeostasis are pancreatic β cells, which sense elevations in plasma glucose and additional dietary components and respond by releasing the appropriate quantity of insulin, ensuring the arrest of hepatic glucose output and glucose uptake in peripheral tissues. Given that β cell failure is associated with the transition from prediabetes to diabetes, improved β cell function ('compensation') has a central role in preventing type 2 diabetes mellitus (T2DM). Recent data have shown that both insulin secretion and β cell mass dynamics are regulated by the liver kinase B1-AMP-activated kinase (LKB1-AMPK) pathway and related kinases of the AMPK family; thus, an improved understanding of the biological roles of AMPK in the β cell is now of considerable interest.
Collapse
Affiliation(s)
- Jillian L Rourke
- Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ONT, M4N 3M5, Canada
| | - Queenie Hu
- Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ONT, M4N 3M5, Canada
| | - Robert A Screaton
- Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ONT, M4N 3M5, Canada; Department of Biochemistry, University of Toronto, Toronto, ONT, M5S 1A8, Canada.
| |
Collapse
|
26
|
Martinez-Sanchez A, Nguyen-Tu MS, Cebola I, Yavari A, Marchetti P, Piemonti L, de Koning E, Shapiro AMJ, Johnson P, Sakamoto K, Smith DM, Leclerc I, Ashrafian H, Ferrer J, Rutter GA. MiR-184 expression is regulated by AMPK in pancreatic islets. FASEB J 2018; 32:2587-2600. [PMID: 29269398 PMCID: PMC6207280 DOI: 10.1096/fj.201701100r] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
AMPK is a critical energy sensor and target for widely used antidiabetic drugs. In β cells, elevated glucose concentrations lower AMPK activity, and the ablation of both catalytic subunits [β-cell–specific AMPK double-knockout (βAMPKdKO) mice] impairs insulin secretion in vivo and β-cell identity. MicroRNAs (miRNAs) are small RNAs that silence gene expression that are essential for pancreatic β-cell function and identity and altered in diabetes. Here, we have explored the miRNAs acting downstream of AMPK in mouse and human β cells. We identified 14 down-regulated and 9 up-regulated miRNAs in βAMPKdKO vs. control islets. Gene ontology analysis of targeted transcripts revealed enrichment in pathways important for β-cell function and identity. The most down-regulated miRNA was miR-184 (miR-184-3p), an important regulator of β-cell function and compensatory expansion that is controlled by glucose and reduced in diabetes. We demonstrate that AMPK is a potent regulator and an important mediator of the negative effects of glucose on miR-184 expression. Additionally, we reveal sexual dimorphism in miR-184 expression in mouse and human islets. Collectively, these data demonstrate that glucose-mediated changes in AMPK activity are central for the regulation of miR-184 and other miRNAs in islets and provide a link between energy status and gene expression in β cells.—Martinez-Sanchez, A., Nguyen-Tu, M.-S., Cebola, I., Yavari, A., Marchetti, P., Piemonti, L., de Koning, E., Shapiro, A. M. J., Johnson, P., Sakamoto, K., Smith, D. M., Leclerc, I., Ashrafian, H., Ferrer, J., Rutter, G. A. MiR-184 expression is regulated by AMPK in pancreatic islets.
Collapse
Affiliation(s)
- Aida Martinez-Sanchez
- Section of Cell Biology and Functional Genomics Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom
| | - Marie-Sophie Nguyen-Tu
- Section of Cell Biology and Functional Genomics Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom
| | - Ines Cebola
- Beta Cell Genome Regulation Laboratory, Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom
| | - Arash Yavari
- Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Piero Marchetti
- Department of Endocrinology and Metabolism, University of Pisa, Pisa, Italy
| | - Lorenzo Piemonti
- San Raffaele Diabetes Research Institute (SR-DRI), Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, Milan, Italy.,Vita-Salute San Raffaele University, Milan, Italy
| | - Eelco de Koning
- Hubrecht Institute, Utrecht, The Netherlands.,Department of Medicine, Leiden University Medical Center, Leiden, The Netherlands
| | - A M James Shapiro
- Clinical Islet Laboratory and Clinical Islet Transplant Program, University of Alberta, Edmonton, Alberta, Canada
| | - Paul Johnson
- Nuffield Department of Surgical Sciences, University of Oxford, Oxford, United Kingdom
| | - Kei Sakamoto
- Nestle Institute of Health Sciences, Lausanne, Switzerland
| | - David M Smith
- AstraZeneca Research and Development, Innovative Medicines and Early Development, Discovery Sciences, Cambridge, United Kingdom
| | - Isabelle Leclerc
- Section of Cell Biology and Functional Genomics Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom
| | - Houman Ashrafian
- Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Jorge Ferrer
- Beta Cell Genome Regulation Laboratory, Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom
| | - Guy A Rutter
- Section of Cell Biology and Functional Genomics Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom
| |
Collapse
|
27
|
A Novel Phenylchromane Derivative Increases the Rate of Glucose Uptake in L6 Myotubes and Augments Insulin Secretion from Pancreatic Beta-Cells by Activating AMPK. Pharm Res 2017; 34:2873-2890. [DOI: 10.1007/s11095-017-2271-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 09/24/2017] [Indexed: 01/04/2023]
|
28
|
Xu C, Liu WB, Zhang DD, Wang KZ, Xia SL, Li XF. Molecular characterization of AMP-activated protein kinase α2 from herbivorous fish Megalobrama amblycephala and responsiveness to glucose loading and dietary carbohydrate levels. Comp Biochem Physiol A Mol Integr Physiol 2017; 208:24-34. [DOI: 10.1016/j.cbpa.2017.03.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 02/24/2017] [Accepted: 03/13/2017] [Indexed: 10/20/2022]
|
29
|
Abstract
The pancreatic β-cell secretes insulin in response to elevated plasma glucose. This review applies an external bioenergetic critique to the central processes of glucose-stimulated insulin secretion, including glycolytic and mitochondrial metabolism, the cytosolic adenine nucleotide pool, and its interaction with plasma membrane ion channels. The control mechanisms responsible for the unique responsiveness of the cell to glucose availability are discussed from bioenergetic and metabolic control standpoints. The concept of coupling factor facilitation of secretion is critiqued, and an attempt is made to unravel the bioenergetic basis of the oscillatory mechanisms controlling secretion. The need to consider the physiological constraints operating in the intact cell is emphasized throughout. The aim is to provide a coherent pathway through an extensive, complex, and sometimes bewildering literature, particularly for those unfamiliar with the field.
Collapse
Affiliation(s)
- David G Nicholls
- Buck Institute for Research on Aging, Novato, California; and Department of Clinical Sciences, Unit of Molecular Metabolism, Lund University Diabetes Centre, Malmo, Sweden
| |
Collapse
|
30
|
Li J, Zhong L, Wang F, Zhu H. Dissecting the role of AMP-activated protein kinase in human diseases. Acta Pharm Sin B 2017; 7:249-259. [PMID: 28540163 PMCID: PMC5430814 DOI: 10.1016/j.apsb.2016.12.003] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 11/12/2016] [Accepted: 11/17/2016] [Indexed: 12/18/2022] Open
Abstract
AMP-activated protein kinase (AMPK), known as a sensor and a master of cellular energy balance, integrates various regulatory signals including anabolic and catabolic metabolic processes. Accompanying the application of genetic methods and a plethora of AMPK agonists, rapid progress has identified AMPK as an attractive therapeutic target for several human diseases, such as cancer, type 2 diabetes, atherosclerosis, myocardial ischemia/reperfusion injury and neurodegenerative disease. The role of AMPK in metabolic and energetic modulation both at the intracellular and whole body levels has been reviewed elsewhere. In the present review, we summarize and update the paradoxical role of AMPK implicated in the diseases mentioned above and put forward the challenge encountered. Thus it will be expected to provide important clues for exploring rational methods of intervention in human diseases.
Collapse
Affiliation(s)
- Jin Li
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China
| | - Liping Zhong
- Life Science College of Tarim University, Xinjiang 843300, China
| | - Fengzhong Wang
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China
- Corresponding author. Tel./fax: +86 10 62810295.
| | - Haibo Zhu
- State Key Laboratory for Bioactive Substances and Functions of Natural Medicines, Beijing 100050, China
- Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study, Beijing 100050, China
- Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
- Corresponding author at: Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China. Tel./fax: +86 10 63188106.
| |
Collapse
|
31
|
Martinez-Sanchez A, Rutter GA, Latreille M. MiRNAs in β-Cell Development, Identity, and Disease. Front Genet 2017; 7:226. [PMID: 28123396 PMCID: PMC5225124 DOI: 10.3389/fgene.2016.00226] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 12/21/2016] [Indexed: 12/22/2022] Open
Abstract
Pancreatic β-cells regulate glucose metabolism by secreting insulin, which in turn stimulates the utilization or storage of the sugar by peripheral tissues. Insulin insufficiency and a prolonged period of insulin resistance are usually the core components of type 2 diabetes (T2D). Although, decreased insulin levels in T2D have long been attributed to a decrease in β-cell function and/or mass, this model has recently been refined with the recognition that a loss of β-cell “identity” and dedifferentiation also contribute to the decline in insulin production. MicroRNAs (miRNAs) are key regulatory molecules that display tissue-specific expression patterns and maintain the differentiated state of somatic cells. During the past few years, great strides have been made in understanding how miRNA circuits impact β-cell identity. Here, we review current knowledge on the role of miRNAs in regulating the acquisition of the β-cell fate during development and in maintaining mature β-cell identity and function during stress situations such as obesity, pregnancy, aging, or diabetes. We also discuss how miRNA function could be harnessed to improve our ability to generate β-cells for replacement therapy for T2D.
Collapse
Affiliation(s)
- Aida Martinez-Sanchez
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London London, UK
| | - Guy A Rutter
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London London, UK
| | - Mathieu Latreille
- Cellular Identity and Metabolism Group, MRC London Institute of Medical SciencesLondon, UK; Institute of Clinical Sciences, Faculty of Medicine, Imperial College LondonLondon, UK
| |
Collapse
|
32
|
Kim JW, You YH, Ham DS, Yang HK, Yoon KH. The Paradoxical Effects of AMPK on Insulin Gene Expression and Glucose-Induced Insulin Secretion. J Cell Biochem 2016; 117:239-46. [PMID: 26105159 DOI: 10.1002/jcb.25271] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 06/19/2015] [Indexed: 12/23/2022]
Abstract
The activation of AMP-activated protein kinase (AMPK) is known to repress the expression of the insulin gene and glucose-stimulated insulin secretion (GSIS). However, the mechanisms by which this occurs, as well as the effects of AMPK activation on glucolipotoxicity-induced β-cell dysfunction, have not been elucidated. To investigate the effects of 5-amino-4-imidazolecarboxamide ribonucleotide (AICAR) and peroxisome proliferator-activated receptorγ-coactivator-1α (PGC-1α) on β-cell-specific genes under glucolipotoxic conditions, we performed real-time PCR and measured insulin secretion by primary islets. To study these effects in vivo, we administered AICAR for 10 days (1 mg/g body weight) to 90% pancreatectomized hyperglycemic mice. The exposure of isolated rat and human islets to glucolipotoxic conditions and the overexpression of PGC-1α suppressed insulin and NEUROD1 mRNA expression. However, the expression of these genes was preserved by AICAR treatment and by PGC-1α inhibition. Exposure of isolated islets to glucolipotoxic conditions for 3 days decreased GSIS, which was also well maintained by AICAR treatment and by PGC-1α inhibition. The administration of AICAR to 90% pancreatectomized hyperglycemic mice improved glucose tolerance and insulin secretion. These results indicate that treatment of islets with an AMPK agonist under glucolipotoxic conditions protects against glucolipotoxicity-induced β-cell dysfunction. A better understanding of the functions of molecules such as PGC-1α and AMPK, which play key roles in intracellular fuel regulation, could herald a new era for the treatment of patients with type 2 diabetes mellitus by providing protection against glucolipotoxicity.
Collapse
Affiliation(s)
- Ji-Won Kim
- Department of Endocrinology & Metabolism, The Catholic University of Korea, Seoul, 137-040, Korea
| | - Young-Hye You
- Department of Endocrinology & Metabolism, The Catholic University of Korea, Seoul, 137-040, Korea
| | - Dong-Sik Ham
- Department of Endocrinology & Metabolism, The Catholic University of Korea, Seoul, 137-040, Korea
| | - Hae Kyung Yang
- Department of Endocrinology & Metabolism, The Catholic University of Korea, Seoul, 137-040, Korea
| | - Kun-Ho Yoon
- Department of Endocrinology & Metabolism, The Catholic University of Korea, Seoul, 137-040, Korea
| |
Collapse
|
33
|
Cheng J, Zhang T, Ji H, Tao K, Guo J, Wei W. Functional characterization of AMP-activated protein kinase signaling in tumorigenesis. Biochim Biophys Acta Rev Cancer 2016; 1866:232-251. [PMID: 27681874 DOI: 10.1016/j.bbcan.2016.09.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 09/22/2016] [Accepted: 09/23/2016] [Indexed: 12/13/2022]
Abstract
AMP-activated protein kinase (AMPK) is a ubiquitously expressed metabolic sensor among various species. Specifically, cellular AMPK is phosphorylated and activated under certain stressful conditions, such as energy deprivation, in turn to activate diversified downstream substrates to modulate the adaptive changes and maintain metabolic homeostasis. Recently, emerging evidences have implicated the potential roles of AMPK signaling in tumor initiation and progression. Nevertheless, a comprehensive description on such topic is still in scarcity, especially in combination of its biochemical features with mouse modeling results to elucidate the physiological role of AMPK signaling in tumorigenesis. Hence, we performed this thorough review by summarizing the tumorigenic role of each component along the AMPK signaling, comprising of both its upstream and downstream effectors. Moreover, their functional interplay with the AMPK heterotrimer and exclusive efficacies in carcinogenesis were chiefly explained among genetically altered mice models. Importantly, the pharmaceutical investigations of AMPK relevant medications have also been highlighted. In summary, in this review, we not only elucidate the potential functions of AMPK signaling pathway in governing tumorigenesis, but also potentiate the future targeted strategy aiming for better treatment of aberrant metabolism-associated diseases, including cancer.
Collapse
Affiliation(s)
- Ji Cheng
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, People's Republic of China; Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Tao Zhang
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Hongbin Ji
- Key Laboratory of Systems Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Science, Shanghai 200031, People's Republic of China
| | - Kaixiong Tao
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, People's Republic of China.
| | - Jianping Guo
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
| | - Wenyi Wei
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
| |
Collapse
|
34
|
Sayers SR, Reimann F, Gribble FM, Parker H, Zac-Varghese S, Bloom SR, Foretz M, Viollet B, Rutter GA. Proglucagon Promoter Cre-Mediated AMPK Deletion in Mice Increases Circulating GLP-1 Levels and Oral Glucose Tolerance. PLoS One 2016; 11:e0149549. [PMID: 27010458 PMCID: PMC4806996 DOI: 10.1371/journal.pone.0149549] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 02/02/2016] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Enteroendocrine L-cells synthesise and release the gut hormone glucagon-like peptide-1 (GLP-1) in response to food transit. Deletion of the tumour suppressor kinase LKB1 from proglucagon-expressing cells leads to the generation of intestinal polyps but no change in circulating GLP-1 levels. Here, we explore the role of the downstream kinase AMP-activated protein kinase (AMPK) in these cells. METHOD Loss of AMPK from proglucagon-expressing cells was achieved using a preproglucagon promoter-driven Cre (iGluCre) to catalyse recombination of floxed alleles of AMPKα1 and α2. Oral and intraperitoneal glucose tolerance were measured using standard protocols. L-cell mass was measured by immunocytochemistry. Hormone and peptide levels were measured by electrochemical-based luminescence detection or radioimmunoassay. RESULTS Recombination with iGluCre led to efficient deletion of AMPK from intestinal L- and pancreatic alpha-cells. In contrast to mice rendered null for LKB1 using the same strategy, mice deleted for AMPK displayed an increase (WT: 0.05 ± 0.01, KO: 0.09±0.02%, p<0.01) in L-cell mass and elevated plasma fasting (WT: 5.62 ± 0.800 pg/ml, KO: 14.5 ± 1.870, p<0.01) and fed (WT: 15.7 ± 1.48pg/ml, KO: 22.0 ± 6.62, p<0.01) GLP-1 levels. Oral, but not intraperitoneal, glucose tolerance was significantly improved by AMPK deletion, whilst insulin and glucagon levels were unchanged despite an increase in alpha to beta cell ratio (WT: 0.23 ± 0.02, KO: 0.33 ± 0.03, p<0.01). CONCLUSION AMPK restricts L-cell growth and GLP-1 secretion to suppress glucose tolerance. Targeted inhibition of AMPK in L-cells may thus provide a new therapeutic strategy in some forms of type 2 diabetes.
Collapse
Affiliation(s)
- Sophie R. Sayers
- Department of Cell Biology and Functional Genomics, Imperial College London, London, W12 ONN, United Kingdom
| | - Frank Reimann
- Wellcome Trust - MRC Institute of Metabolic Science, University of Cambridge, Hills Road, Cambridge, CB2 0QQ, United Kingdom
| | - Fiona M. Gribble
- Wellcome Trust - MRC Institute of Metabolic Science, University of Cambridge, Hills Road, Cambridge, CB2 0QQ, United Kingdom
| | - Helen Parker
- Wellcome Trust - MRC Institute of Metabolic Science, University of Cambridge, Hills Road, Cambridge, CB2 0QQ, United Kingdom
| | - Sagen Zac-Varghese
- Department of Investigative Medicine, Imperial College London, London, W12 ONN, United Kingdom
| | - Stephen R. Bloom
- Department of Investigative Medicine, Imperial College London, London, W12 ONN, United Kingdom
| | - Marc Foretz
- INSERM, U1016, Institut Cochin, 75014 Paris, France
- CNRS, UMR8104, 75014 Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, 75014 Paris, France
| | - Benoit Viollet
- INSERM, U1016, Institut Cochin, 75014 Paris, France
- CNRS, UMR8104, 75014 Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, 75014 Paris, France
| | - Guy A. Rutter
- Department of Cell Biology and Functional Genomics, Imperial College London, London, W12 ONN, United Kingdom
- * E-mail:
| |
Collapse
|
35
|
Abstract
AMPK is an evolutionary conserved energy sensor involved in the regulation of energy metabolism. Based on biochemical studies, AMPK has brought much of interest in recent years due to its potential impact on metabolic disorders. Suitable animal models are therefore essential to promote our understanding of the molecular and functional roles of AMPK but also to bring novel information for the development of novel therapeutic strategies. The organism systems include pig (Sus scrofa), mouse (Mus musculus), fly (Drosophila melanogaster), worm (Caenorhabditis elegans), and fish (Danio rerio) models. These animal models have provided reliable experimental evidence demonstrating the crucial role of AMPK in the regulation of metabolism but also of cell polarity, autophagy, and oxidative stress. In this chapter, we update the new development in the generation and application of animal models for the study of AMPK biology. We also discuss recent breakthroughs from studies in mice, flies, and worms showing how AMPK has a primary role in initiating or promoting pathological or beneficial impact on health.
Collapse
Affiliation(s)
- Benoit Viollet
- INSERM U1016, Institut Cochin, Paris, France. .,CNRS UMR 8104, Paris, France. .,Université Paris Descartes, Sorbonne Paris Cité, Paris, France.
| | - Marc Foretz
- INSERM U1016, Institut Cochin, Paris, France.,CNRS UMR 8104, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| |
Collapse
|
36
|
Scoville DW, Cyphert HA, Liao L, Xu J, Reynolds A, Guo S, Stein R. MLL3 and MLL4 Methyltransferases Bind to the MAFA and MAFB Transcription Factors to Regulate Islet β-Cell Function. Diabetes 2015; 64:3772-83. [PMID: 26180087 PMCID: PMC4613979 DOI: 10.2337/db15-0281] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 07/03/2015] [Indexed: 12/19/2022]
Abstract
Insulin produced by islet β-cells plays a critical role in glucose homeostasis, with type 1 and type 2 diabetes both resulting from inactivation and/or loss of this cell population. Islet-enriched transcription factors regulate β-cell formation and function, yet little is known about the molecules recruited to mediate control. An unbiased in-cell biochemical and mass spectrometry strategy was used to isolate MafA transcription factor-binding proteins. Among the many coregulators identified were all of the subunits of the mixed-lineage leukemia 3 (Mll3) and 4 (Mll4) complexes, with histone 3 lysine 4 methyltransferases strongly associated with gene activation. MafA was bound to the ∼1.5 MDa Mll3 and Mll4 complexes in size-fractionated β-cell extracts. Likewise, closely related human MAFB, which is important to β-cell formation and coproduced with MAFA in adult human islet β-cells, bound MLL3 and MLL4 complexes. Knockdown of NCOA6, a core subunit of these methyltransferases, reduced expression of a subset of MAFA and MAFB target genes in mouse and human β-cell lines. In contrast, a broader effect on MafA/MafB gene activation was observed in mice lacking NCoA6 in islet β-cells. We propose that MLL3 and MLL4 are broadly required for controlling MAFA and MAFB transactivation during development and postnatally.
Collapse
Affiliation(s)
- David W Scoville
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN
| | - Holly A Cyphert
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN
| | - Lan Liao
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX
| | - Jianming Xu
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX
| | - Al Reynolds
- Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, TN
| | - Shuangli Guo
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN
| | - Roland Stein
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN
| |
Collapse
|
37
|
Shi YC, Loh K, Bensellam M, Lee K, Zhai L, Lau J, Cantley J, Luzuriaga J, Laybutt DR, Herzog H. Pancreatic PYY Is Critical in the Control of Insulin Secretion and Glucose Homeostasis in Female Mice. Endocrinology 2015; 156:3122-36. [PMID: 26125465 DOI: 10.1210/en.2015-1168] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Insulin secretion is tightly controlled through coordinated actions of a number of systemic and local factors. Peptide YY (PYY) is expressed in α-cells of the islet, but its role in control of islet function such as insulin release is not clear. In this study, we generated a transgenic mouse model (Pyy(tg/+)/Rip-Cre) overexpressing the Pyy gene under the control of the rat insulin 2 gene promoter and assessed the impact of islet-released PYY on β-cell function, insulin release, and glucose homeostasis in mice. Our results show that up-regulation of PYY in islet β-cells leads to an increase in serum insulin levels as well as improved glucose tolerance. Interestingly, PYY-overproducing mice show increased lean mass and reduced fat mass with no significant changes in food intake or body weight. Energy expenditure is also increased accompanied by increased respiratory exchange ratio. Mechanistically, the enhanced insulin levels and improved glucose tolerance are primarily due to increased β-cell mass and secretion. This is associated with alterations in the expression of genes important for β-cell proliferation and function as well as the maintenance of the β-cell phenotype. Taken together, these data demonstrate that pancreatic islet-derived PYY plays an important role in controlling glucose homeostasis through the modulation of β-cell mass and function.
Collapse
Affiliation(s)
- Yan-Chuan Shi
- Neuroscience (Y.-C.S., K.Lo., K.Le., L.Z., J.La., H.H.) and Diabetes and Metabolism (M.B., J.C., J.Lu., D.R.L.) Divisions, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst NSW 2010, Sydney, Australia; Faculty of Medicine (Y.-C.S., K.Lo., J.C., D.R.L., H.H.), UNSW Australia, Sydney, NSW, 2052 Australia; and Department of Physiology, Anatomy and Genetics (J.C.), University of Oxford, Oxford, OX1 3QX United Kingdom
| | - Kim Loh
- Neuroscience (Y.-C.S., K.Lo., K.Le., L.Z., J.La., H.H.) and Diabetes and Metabolism (M.B., J.C., J.Lu., D.R.L.) Divisions, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst NSW 2010, Sydney, Australia; Faculty of Medicine (Y.-C.S., K.Lo., J.C., D.R.L., H.H.), UNSW Australia, Sydney, NSW, 2052 Australia; and Department of Physiology, Anatomy and Genetics (J.C.), University of Oxford, Oxford, OX1 3QX United Kingdom
| | - Mohammed Bensellam
- Neuroscience (Y.-C.S., K.Lo., K.Le., L.Z., J.La., H.H.) and Diabetes and Metabolism (M.B., J.C., J.Lu., D.R.L.) Divisions, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst NSW 2010, Sydney, Australia; Faculty of Medicine (Y.-C.S., K.Lo., J.C., D.R.L., H.H.), UNSW Australia, Sydney, NSW, 2052 Australia; and Department of Physiology, Anatomy and Genetics (J.C.), University of Oxford, Oxford, OX1 3QX United Kingdom
| | - Kailun Lee
- Neuroscience (Y.-C.S., K.Lo., K.Le., L.Z., J.La., H.H.) and Diabetes and Metabolism (M.B., J.C., J.Lu., D.R.L.) Divisions, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst NSW 2010, Sydney, Australia; Faculty of Medicine (Y.-C.S., K.Lo., J.C., D.R.L., H.H.), UNSW Australia, Sydney, NSW, 2052 Australia; and Department of Physiology, Anatomy and Genetics (J.C.), University of Oxford, Oxford, OX1 3QX United Kingdom
| | - Lei Zhai
- Neuroscience (Y.-C.S., K.Lo., K.Le., L.Z., J.La., H.H.) and Diabetes and Metabolism (M.B., J.C., J.Lu., D.R.L.) Divisions, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst NSW 2010, Sydney, Australia; Faculty of Medicine (Y.-C.S., K.Lo., J.C., D.R.L., H.H.), UNSW Australia, Sydney, NSW, 2052 Australia; and Department of Physiology, Anatomy and Genetics (J.C.), University of Oxford, Oxford, OX1 3QX United Kingdom
| | - Jackie Lau
- Neuroscience (Y.-C.S., K.Lo., K.Le., L.Z., J.La., H.H.) and Diabetes and Metabolism (M.B., J.C., J.Lu., D.R.L.) Divisions, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst NSW 2010, Sydney, Australia; Faculty of Medicine (Y.-C.S., K.Lo., J.C., D.R.L., H.H.), UNSW Australia, Sydney, NSW, 2052 Australia; and Department of Physiology, Anatomy and Genetics (J.C.), University of Oxford, Oxford, OX1 3QX United Kingdom
| | - James Cantley
- Neuroscience (Y.-C.S., K.Lo., K.Le., L.Z., J.La., H.H.) and Diabetes and Metabolism (M.B., J.C., J.Lu., D.R.L.) Divisions, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst NSW 2010, Sydney, Australia; Faculty of Medicine (Y.-C.S., K.Lo., J.C., D.R.L., H.H.), UNSW Australia, Sydney, NSW, 2052 Australia; and Department of Physiology, Anatomy and Genetics (J.C.), University of Oxford, Oxford, OX1 3QX United Kingdom
| | - Jude Luzuriaga
- Neuroscience (Y.-C.S., K.Lo., K.Le., L.Z., J.La., H.H.) and Diabetes and Metabolism (M.B., J.C., J.Lu., D.R.L.) Divisions, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst NSW 2010, Sydney, Australia; Faculty of Medicine (Y.-C.S., K.Lo., J.C., D.R.L., H.H.), UNSW Australia, Sydney, NSW, 2052 Australia; and Department of Physiology, Anatomy and Genetics (J.C.), University of Oxford, Oxford, OX1 3QX United Kingdom
| | - D Ross Laybutt
- Neuroscience (Y.-C.S., K.Lo., K.Le., L.Z., J.La., H.H.) and Diabetes and Metabolism (M.B., J.C., J.Lu., D.R.L.) Divisions, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst NSW 2010, Sydney, Australia; Faculty of Medicine (Y.-C.S., K.Lo., J.C., D.R.L., H.H.), UNSW Australia, Sydney, NSW, 2052 Australia; and Department of Physiology, Anatomy and Genetics (J.C.), University of Oxford, Oxford, OX1 3QX United Kingdom
| | - Herbert Herzog
- Neuroscience (Y.-C.S., K.Lo., K.Le., L.Z., J.La., H.H.) and Diabetes and Metabolism (M.B., J.C., J.Lu., D.R.L.) Divisions, Garvan Institute of Medical Research, St Vincent's Hospital, Darlinghurst NSW 2010, Sydney, Australia; Faculty of Medicine (Y.-C.S., K.Lo., J.C., D.R.L., H.H.), UNSW Australia, Sydney, NSW, 2052 Australia; and Department of Physiology, Anatomy and Genetics (J.C.), University of Oxford, Oxford, OX1 3QX United Kingdom
| |
Collapse
|
38
|
Matsuda T, Takahashi H, Mieda Y, Shimizu S, Kawamoto T, Matsuura Y, Takai T, Suzuki E, Kanno A, Koyanagi-Kimura M, Asahara SI, Bartolome A, Yokoi N, Inoue H, Ogawa W, Seino S, Kido Y. Regulation of Pancreatic β Cell Mass by Cross-Interaction between CCAAT Enhancer Binding Protein β Induced by Endoplasmic Reticulum Stress and AMP-Activated Protein Kinase Activity. PLoS One 2015; 10:e0130757. [PMID: 26091000 PMCID: PMC4474801 DOI: 10.1371/journal.pone.0130757] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 05/22/2015] [Indexed: 01/05/2023] Open
Abstract
During the development of type 2 diabetes, endoplasmic reticulum (ER) stress leads to not only insulin resistance but also to pancreatic beta cell failure. Conversely, cell function under various stressed conditions can be restored by reducing ER stress by activating AMP-activated protein kinase (AMPK). However, the details of this mechanism are still obscure. Therefore, the current study aims to elucidate the role of AMPK activity during ER stress-associated pancreatic beta cell failure. MIN6 cells were loaded with 5-amino-1-β-D-ribofuranosyl-imidazole-4-carboxamide (AICAR) and metformin to assess the relationship between AMPK activity and CCAAT enhancer binding protein β (C/EBPβ) expression levels. The effect of C/EBPβ phosphorylation on expression levels was also investigated. Vildagliptin and metformin were administered to pancreatic beta cell-specific C/EBPβ transgenic mice to investigate the relationship between C/EBPβ expression levels and AMPK activity in the pancreatic islets. When pancreatic beta cells are exposed to ER stress, the accumulation of the transcription factor C/EBPβ lowers the AMP/ATP ratio, thereby decreasing AMPK activity. In an opposite manner, incubation of MIN6 cells with AICAR or metformin activated AMPK, which suppressed C/EBPβ expression. In addition, administration of the dipeptidyl peptidase-4 inhibitor vildagliptin and metformin to pancreatic beta cell-specific C/EBPβ transgenic mice decreased C/EBPβ expression levels and enhanced pancreatic beta cell mass in proportion to the recovery of AMPK activity. Enhanced C/EBPβ expression and decreased AMPK activity act synergistically to induce ER stress-associated pancreatic beta cell failure.
Collapse
Affiliation(s)
- Tomokazu Matsuda
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Hiroaki Takahashi
- Division of Medical Chemistry, Department of Biophysics, Kobe University Graduate School of Health Sciences, Kobe, Japan
| | - Yusuke Mieda
- Division of Medical Chemistry, Department of Biophysics, Kobe University Graduate School of Health Sciences, Kobe, Japan
| | - Shinobu Shimizu
- Division of Medical Chemistry, Department of Biophysics, Kobe University Graduate School of Health Sciences, Kobe, Japan
| | - Takeshi Kawamoto
- Division of Medical Chemistry, Department of Biophysics, Kobe University Graduate School of Health Sciences, Kobe, Japan
| | - Yuki Matsuura
- Division of Medical Chemistry, Department of Biophysics, Kobe University Graduate School of Health Sciences, Kobe, Japan
| | - Tomoko Takai
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Emi Suzuki
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Ayumi Kanno
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Maki Koyanagi-Kimura
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Shun-ichiro Asahara
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Alberto Bartolome
- Naomi Berrie Diabetes Center, Department of Medicine, Columbia University, New York, United States of America
| | - Norihide Yokoi
- Division of Molecular and Metabolic Medicine, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Hiroshi Inoue
- Department of Physiology and Metabolism, Brain/Liver Interface Medicine Research Center, Kanazawa University, Kanazawa, Japan
| | - Wataru Ogawa
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Susumu Seino
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
- Division of Molecular and Metabolic Medicine, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Yoshiaki Kido
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
- Division of Medical Chemistry, Department of Biophysics, Kobe University Graduate School of Health Sciences, Kobe, Japan
- * E-mail:
| |
Collapse
|
39
|
Inhibition of AMP-Activated Protein Kinase at the Allosteric Drug-Binding Site Promotes Islet Insulin Release. ACTA ACUST UNITED AC 2015; 22:705-11. [DOI: 10.1016/j.chembiol.2015.05.011] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2014] [Revised: 05/05/2015] [Accepted: 05/18/2015] [Indexed: 11/22/2022]
|
40
|
Pancreatic β-cell identity, glucose sensing and the control of insulin secretion. Biochem J 2015; 466:203-18. [PMID: 25697093 DOI: 10.1042/bj20141384] [Citation(s) in RCA: 251] [Impact Index Per Article: 27.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Insulin release from pancreatic β-cells is required to maintain normal glucose homoeostasis in man and many other animals. Defective insulin secretion underlies all forms of diabetes mellitus, a disease currently reaching epidemic proportions worldwide. Although the destruction of β-cells is responsible for Type 1 diabetes (T1D), both lowered β-cell mass and loss of secretory function are implicated in Type 2 diabetes (T2D). Emerging results suggest that a functional deficiency, involving de-differentiation of the mature β-cell towards a more progenitor-like state, may be an important driver for impaired secretion in T2D. Conversely, at least in rodents, reprogramming of islet non-β to β-cells appears to occur spontaneously in models of T1D, and may occur in man. In the present paper, we summarize the biochemical properties which define the 'identity' of the mature β-cell as a glucose sensor par excellence. In particular, we discuss the importance of suppressing a group of 11 'disallowed' housekeeping genes, including Ldha and the monocarboxylate transporter Mct1 (Slc16a1), for normal nutrient sensing. We then survey the changes in the expression and/or activity of β-cell-enriched transcription factors, including FOXO1, PDX1, NKX6.1, MAFA and RFX6, as well as non-coding RNAs, which may contribute to β-cell de-differentiation and functional impairment in T2D. The relevance of these observations for the development of new approaches to treat T1D and T2D is considered.
Collapse
|
41
|
Sun G, da Silva Xavier G, Gorman T, Priest C, Solomou A, Hodson DJ, Foretz M, Viollet B, Herrera PL, Parker H, Reimann F, Gribble FM, Migrenne S, Magnan C, Marley A, Rutter GA. LKB1 and AMPKα1 are required in pancreatic alpha cells for the normal regulation of glucagon secretion and responses to hypoglycemia. Mol Metab 2015; 4:277-86. [PMID: 25830091 PMCID: PMC4354920 DOI: 10.1016/j.molmet.2015.01.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Revised: 01/14/2015] [Accepted: 01/17/2015] [Indexed: 10/24/2022] Open
Abstract
AIMS/HYPOTHESIS Glucagon release from pancreatic alpha cells is required for normal glucose homoeostasis and is dysregulated in both Type 1 and Type 2 diabetes. The tumour suppressor LKB1 (STK11) and the downstream kinase AMP-activated protein kinase (AMPK), modulate cellular metabolism and growth, and AMPK is an important target of the anti-hyperglycaemic agent metformin. While LKB1 and AMPK have emerged recently as regulators of beta cell mass and insulin secretion, the role of these enzymes in the control of glucagon production in vivo is unclear. METHODS Here, we ablated LKB1 (αLKB1KO), or the catalytic alpha subunits of AMPK (αAMPKdKO, -α1KO, -α2KO), selectively in ∼45% of alpha cells in mice by deleting the corresponding flox'd alleles with a preproglucagon promoter (PPG) Cre. RESULTS Blood glucose levels in male αLKB1KO mice were lower during intraperitoneal glucose, aminoimidazole carboxamide ribonucleotide (AICAR) or arginine tolerance tests, and glucose infusion rates were increased in hypoglycemic clamps (p < 0.01). αLKB1KO mice also displayed impaired hypoglycemia-induced glucagon release. Glucose infusion rates were also elevated (p < 0.001) in αAMPKα1 null mice, and hypoglycemia-induced plasma glucagon increases tended to be lower (p = 0.06). Glucagon secretion from isolated islets was sensitized to the inhibitory action of glucose in αLKB1KO, αAMPKdKO, and -α1KO, but not -α2KO islets. CONCLUSIONS/INTERPRETATION An LKB1-dependent signalling cassette, involving but not restricted to AMPKα1, is required in pancreatic alpha cells for the control of glucagon release by glucose.
Collapse
Affiliation(s)
- Gao Sun
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, UK
| | - Gabriela da Silva Xavier
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, UK
| | | | | | - Antonia Solomou
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, UK
| | - David J. Hodson
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, UK
| | - Marc Foretz
- Inserm, U1016, Institut Cochin, Paris, France
- CNRS, UMR8104, Paris, France
- Université Paris Descartes, Sorbonne Paris cité, Paris, France
| | - Benoit Viollet
- Inserm, U1016, Institut Cochin, Paris, France
- CNRS, UMR8104, Paris, France
- Université Paris Descartes, Sorbonne Paris cité, Paris, France
| | - Pedro-Luis Herrera
- Department of Genetic Medicine & Development, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Helen Parker
- Cambridge Institute for Medical Research, Addenbrooke's Hospital, Cambridge, UK
| | - Frank Reimann
- Cambridge Institute for Medical Research, Addenbrooke's Hospital, Cambridge, UK
| | - Fiona M. Gribble
- Cambridge Institute for Medical Research, Addenbrooke's Hospital, Cambridge, UK
| | - Stephanie Migrenne
- University Paris Diderot-Paris 7-Unit of Functional and Adaptive Biology (BFA) EAC 7059C NRS, France
| | - Christophe Magnan
- University Paris Diderot-Paris 7-Unit of Functional and Adaptive Biology (BFA) EAC 7059C NRS, France
| | | | - Guy A. Rutter
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, UK
| |
Collapse
|
42
|
Boullerne AI, Skias D, Hartman EM, Testai FD, Kalinin S, Polak PE, Feinstein DL. A single-nucleotide polymorphism in serine-threonine kinase 11, the gene encoding liver kinase B1, is a risk factor for multiple sclerosis. ASN Neuro 2015; 7:1759091415568914. [PMID: 25694554 PMCID: PMC4342367 DOI: 10.1177/1759091415568914] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
We identified a family in which five siblings were diagnosed with multiple sclerosis (MS) or clinically isolated syndrome. Several women in the maternal lineage have comorbidities typically associated with Peutz Jeghers Syndrome, a rare autosomal-dominant disease caused by mutations in the serine-threonine-kinase 11 (STK11) gene, which encodes liver kinase B1. Sequence analysis of DNA from one sibling identified a single-nucleotide polymorphism (SNP) within STK11 intron 5. This SNP (dbSNP ID: rs9282860) was identified by TaqMan polymerase chain reaction (PCR) assays in DNA samples available from two other siblings. Further screening was carried out in samples from 654 relapsing-remitting MS patients, 100 primary progressive MS patients, and 661 controls. The STK11-SNP has increased frequency in all female patients versus controls (odds ratio = 1.66, 95% CI = 1.05, 2.64, p = .032). The STK11-SNP was not associated with disease duration or onset; however, it was significantly associated with reduced severity (assessed by MS severity scores), with the lowest scores in patients who also harbored the HLA-DRB1*1501 allele. In vitro studies showed that peripheral blood mononuclear cells from members of the family were more sensitive to the mitochondrial inhibitor metformin than cells from MS patients with the major STK11 allele. The increased association of SNP rs9282860 in women with MS defines this variant as a genetic risk factor. The lower disease severity observed in the context of HLA-DRB1*1501 combined with limited in vitro studies raises the provocative possibility that cells harboring the STK11-SNP could be targeted by drugs which increase metabolic stress.
Collapse
Affiliation(s)
- Anne I Boullerne
- Department of Anesthesiology, University of Illinois at Chicago, IL, USA
| | - Demetrios Skias
- Department of Veterans Affairs, Jesse Brown VA Medical Center, Chicago, IL, USA Department of Neurology, University of Illinois at Chicago, IL, USA
| | | | | | - Sergey Kalinin
- Department of Anesthesiology, University of Illinois at Chicago, IL, USA
| | - Paul E Polak
- Department of Anesthesiology, University of Illinois at Chicago, IL, USA
| | - Douglas L Feinstein
- Department of Anesthesiology, University of Illinois at Chicago, IL, USA Department of Veterans Affairs, Jesse Brown VA Medical Center, Chicago, IL, USA
| |
Collapse
|
43
|
Gregg B, Elghazi L, Alejandro EU, Smith MR, Blandino-Rosano M, El-Gabri D, Cras-Méneur C, Bernal-Mizrachi E. Exposure of mouse embryonic pancreas to metformin enhances the number of pancreatic progenitors. Diabetologia 2014; 57:2566-75. [PMID: 25249235 PMCID: PMC4417192 DOI: 10.1007/s00125-014-3379-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Accepted: 08/28/2014] [Indexed: 01/23/2023]
Abstract
AIMS/HYPOTHESIS Developing beta cells are vulnerable to nutrient environmental signals. Early developmental processes that alter the number of pancreatic progenitors can determine the number of beta cells present at birth. Metformin, the most widely used oral agent for treating diabetes, alters intracellular energy status in part by increasing AMP-activated protein kinase (AMPK) signalling. This study examined the effect of metformin on developing pancreas and beta cells. METHODS Pancreatic rudiments from CD-1 mice at embryonic day 13.0 (E13.0) were cultured with metformin, 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR, an AMPK activator) or vehicle control in vitro. In another set of studies, pregnant C57BL/6 mice were treated with metformin throughout gestation. Embryonic (E14.0) and neonatal pancreases were then analysed for their morphometry. RESULTS In vitro metformin treatment led to an increase in the proliferation and number of pancreatic duodenal homeobox 1-positive (PDX1(+)) progenitors. These results were reproduced by in vitro culture of embryonic pancreas rudiments with AICAR, suggesting that AMPK activation was involved. Similarly, metformin administration to pregnant dams induced an increase in both PDX1(+) and neurogenin 3-positive progenitors in the embryonic pancreas at E14.0 and these changes resulted in an increased beta cell fraction in neonates. CONCLUSIONS/INTERPRETATION These results indicate that exposure to metformin during gestation modulates the early steps of beta cell development (prior to E14.0) towards an increase in the number of pancreatic and endocrine progenitors. These changes ultimately result in a higher beta cell fraction at birth. These findings are of clinical importance given that metformin is currently used for the treatment of gestational diabetes.
Collapse
Affiliation(s)
- Brigid Gregg
- Department of Pediatrics, Division of Endocrinology, Diabetes and Metabolism, University of Michigan, Ann Arbor, Michigan, USA
| | - Lynda Elghazi
- Department of Internal Medicine, Division of Metabolism, Endocrinology and Diabetes, Brehm Center for Diabetes Research, University of Michigan, Ann Arbor, Michigan, USA
| | - Emilyn U. Alejandro
- Department of Internal Medicine, Division of Metabolism, Endocrinology and Diabetes, Brehm Center for Diabetes Research, University of Michigan, Ann Arbor, Michigan, USA
| | - Michelle R. Smith
- Department of Pediatrics, Division of Endocrinology, Diabetes and Metabolism, University of Michigan, Ann Arbor, Michigan, USA
- Department of Internal Medicine, Division of Metabolism, Endocrinology and Diabetes, Brehm Center for Diabetes Research, University of Michigan, Ann Arbor, Michigan, USA
| | - Manuel Blandino-Rosano
- Department of Internal Medicine, Division of Metabolism, Endocrinology and Diabetes, Brehm Center for Diabetes Research, University of Michigan, Ann Arbor, Michigan, USA
| | - Deena El-Gabri
- Department of Pediatrics, Division of Endocrinology, Diabetes and Metabolism, University of Michigan, Ann Arbor, Michigan, USA
| | - Corentin Cras-Méneur
- Department of Internal Medicine, Division of Metabolism, Endocrinology and Diabetes, Brehm Center for Diabetes Research, University of Michigan, Ann Arbor, Michigan, USA
| | - Ernesto Bernal-Mizrachi
- Department of Internal Medicine, Division of Metabolism, Endocrinology and Diabetes, Brehm Center for Diabetes Research, University of Michigan, Ann Arbor, Michigan, USA
- VA Ann Arbor Healthcare System, Ann Arbor, Michigan
- Corresponding author: Dr. Ernesto Bernal-Mizrachi VA Ann Arbor Healthcare System, Ann Arbor, Michigan., Department of Internal Medicine, Division of Metabolism, Endocrinology and Diabetes, University of Michigan, Ann Arbor, Michigan 48109-0678, USA., Phone: +1 (734) 615-0262, Fax: +1 (734) 936-6684,
| |
Collapse
|
44
|
Lelliott CJ, Ahnmark A, Admyre T, Ahlstedt I, Irving L, Keyes F, Patterson L, Mumphrey MB, Bjursell M, Gorman T, Bohlooly-Y M, Buchanan A, Harrison P, Vaughan T, Berthoud HR, Lindén D. Monoclonal antibody targeting of fibroblast growth factor receptor 1c ameliorates obesity and glucose intolerance via central mechanisms. PLoS One 2014; 9:e112109. [PMID: 25427253 PMCID: PMC4245083 DOI: 10.1371/journal.pone.0112109] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Accepted: 10/13/2014] [Indexed: 12/21/2022] Open
Abstract
We have generated a novel monoclonal antibody targeting human FGFR1c (R1c mAb) that caused profound body weight and body fat loss in diet-induced obese mice due to decreased food intake (with energy expenditure unaltered), in turn improving glucose control. R1c mAb also caused weight loss in leptin-deficient ob/ob mice, leptin receptor-mutant db/db mice, and in mice lacking either the melanocortin 4 receptor or the melanin-concentrating hormone receptor 1. In addition, R1c mAb did not change hypothalamic mRNA expression levels of Agrp, Cart, Pomc, Npy, Crh, Mch, or Orexin, suggesting that R1c mAb could cause food intake inhibition and body weight loss via other mechanisms in the brain. Interestingly, peripherally administered R1c mAb accumulated in the median eminence, adjacent arcuate nucleus and in the circumventricular organs where it activated the early response gene c-Fos. As a plausible mechanism and coinciding with the initiation of food intake suppression, R1c mAb induced hypothalamic expression levels of the cytokines Monocyte chemoattractant protein 1 and 3 and ERK1/2 and p70 S6 kinase 1 activation.
Collapse
MESH Headings
- Animals
- Antibodies, Monoclonal/pharmacology
- Arcuate Nucleus of Hypothalamus/drug effects
- Arcuate Nucleus of Hypothalamus/metabolism
- Arcuate Nucleus of Hypothalamus/physiopathology
- Chemokine CCL2/agonists
- Chemokine CCL2/genetics
- Chemokine CCL2/metabolism
- Chemokine CCL7/agonists
- Chemokine CCL7/genetics
- Chemokine CCL7/metabolism
- Circumventricular Organs/drug effects
- Circumventricular Organs/metabolism
- Circumventricular Organs/physiopathology
- Eating/drug effects
- Energy Metabolism
- Female
- Gene Expression Regulation
- Glucose Intolerance/drug therapy
- Glucose Intolerance/genetics
- Glucose Intolerance/metabolism
- Glucose Intolerance/physiopathology
- Humans
- Hypothalamus/drug effects
- Hypothalamus/metabolism
- Hypothalamus/physiopathology
- Leptin/deficiency
- Leptin/genetics
- Mice
- Mice, Knockout
- Mice, Obese
- Mitogen-Activated Protein Kinases/genetics
- Mitogen-Activated Protein Kinases/metabolism
- Obesity/drug therapy
- Obesity/genetics
- Obesity/metabolism
- Obesity/physiopathology
- Receptor, Fibroblast Growth Factor, Type 1/antagonists & inhibitors
- Receptor, Fibroblast Growth Factor, Type 1/genetics
- Receptor, Fibroblast Growth Factor, Type 1/metabolism
- Receptor, Melanocortin, Type 4/deficiency
- Receptor, Melanocortin, Type 4/genetics
- Receptors, Somatostatin/deficiency
- Receptors, Somatostatin/genetics
- Ribosomal Protein S6 Kinases, 70-kDa/genetics
- Ribosomal Protein S6 Kinases, 70-kDa/metabolism
- Serum Response Factor/agonists
- Serum Response Factor/genetics
- Serum Response Factor/metabolism
- Signal Transduction
Collapse
Affiliation(s)
- Christopher J. Lelliott
- Cardiovascular & Metabolic Disease Innovative Medicines, Dept of Bioscience Diabetes, AstraZeneca, Mölndal, Sweden
| | - Andrea Ahnmark
- Cardiovascular & Metabolic Disease Innovative Medicines, Dept of Bioscience Diabetes, AstraZeneca, Mölndal, Sweden
| | - Therese Admyre
- Discovery Sciences Transgenics, AstraZeneca, Mölndal, Sweden
| | - Ingela Ahlstedt
- Cardiovascular & Metabolic Disease Innovative Medicines, Dept of Bioscience Diabetes, AstraZeneca, Mölndal, Sweden
| | - Lorraine Irving
- Antibody Discovery and Protein Engineering, MedImmune, Cambridge, United Kingdom
| | - Feenagh Keyes
- Antibody Discovery and Protein Engineering, MedImmune, Cambridge, United Kingdom
| | - Laurel Patterson
- Neurobiology of Nutrition Laboratory, Pennington Biomedical Research Center, Baton Rouge, United States of America
| | - Michael B. Mumphrey
- Neurobiology of Nutrition Laboratory, Pennington Biomedical Research Center, Baton Rouge, United States of America
| | - Mikael Bjursell
- Discovery Sciences Transgenics, AstraZeneca, Mölndal, Sweden
| | - Tracy Gorman
- AstraZeneca, Discovery Sciences, Mereside, Alderley Park, Macclesfield, Cheshire, United Kingdom
| | | | - Andrew Buchanan
- Antibody Discovery and Protein Engineering, MedImmune, Cambridge, United Kingdom
| | - Paula Harrison
- Antibody Discovery and Protein Engineering, MedImmune, Cambridge, United Kingdom
| | - Tristan Vaughan
- Antibody Discovery and Protein Engineering, MedImmune, Cambridge, United Kingdom
| | - Hans-Rudolf Berthoud
- Neurobiology of Nutrition Laboratory, Pennington Biomedical Research Center, Baton Rouge, United States of America
| | - Daniel Lindén
- Cardiovascular & Metabolic Disease Innovative Medicines, Dept of Bioscience Diabetes, AstraZeneca, Mölndal, Sweden
- * E-mail:
| |
Collapse
|
45
|
Kone M, Pullen TJ, Sun G, Ibberson M, Martinez-Sanchez A, Sayers S, Nguyen-Tu MS, Kantor C, Swisa A, Dor Y, Gorman T, Ferrer J, Thorens B, Reimann F, Gribble F, McGinty JA, Chen L, French PM, Birzele F, Hildebrandt T, Uphues I, Rutter GA. LKB1 and AMPK differentially regulate pancreatic β-cell identity. FASEB J 2014; 28:4972-85. [PMID: 25070369 PMCID: PMC4377859 DOI: 10.1096/fj.14-257667] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Accepted: 07/14/2014] [Indexed: 12/15/2022]
Abstract
Fully differentiated pancreatic β cells are essential for normal glucose homeostasis in mammals. Dedifferentiation of these cells has been suggested to occur in type 2 diabetes, impairing insulin production. Since chronic fuel excess ("glucotoxicity") is implicated in this process, we sought here to identify the potential roles in β-cell identity of the tumor suppressor liver kinase B1 (LKB1/STK11) and the downstream fuel-sensitive kinase, AMP-activated protein kinase (AMPK). Highly β-cell-restricted deletion of each kinase in mice, using an Ins1-controlled Cre, was therefore followed by physiological, morphometric, and massive parallel sequencing analysis. Loss of LKB1 strikingly (2.0-12-fold, E<0.01) increased the expression of subsets of hepatic (Alb, Iyd, Elovl2) and neuronal (Nptx2, Dlgap2, Cartpt, Pdyn) genes, enhancing glutamate signaling. These changes were partially recapitulated by the loss of AMPK, which also up-regulated β-cell "disallowed" genes (Slc16a1, Ldha, Mgst1, Pdgfra) 1.8- to 3.4-fold (E < 0.01). Correspondingly, targeted promoters were enriched for neuronal (Zfp206; P = 1.3 × 10(-33)) and hypoxia-regulated (HIF1; P = 2.5 × 10(-16)) transcription factors. In summary, LKB1 and AMPK, through only partly overlapping mechanisms, maintain β-cell identity by suppressing alternate pathways leading to neuronal, hepatic, and other characteristics. Selective targeting of these enzymes may provide a new approach to maintaining β-cell function in some forms of diabetes.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | - Avital Swisa
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Yuval Dor
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Tracy Gorman
- AstraZeneca Diabetes and Obesity Drug Discovery, Alderley Edge, UK
| | - Jorge Ferrer
- Section of β-Cell Development, Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, and
| | - Bernard Thorens
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Frank Reimann
- Metabolic Research Laboratories, University of Cambridge, Cambridge, UK and
| | - Fiona Gribble
- Metabolic Research Laboratories, University of Cambridge, Cambridge, UK and
| | - James A McGinty
- Photonics Group, Department of Physics, Imperial College London, London, UK
| | - Lingling Chen
- Photonics Group, Department of Physics, Imperial College London, London, UK
| | - Paul M French
- Photonics Group, Department of Physics, Imperial College London, London, UK
| | | | | | - Ingo Uphues
- Boehringer Ingelheim Pharma, Ingelheim, Germany
| | | |
Collapse
|
46
|
Mitchell RK, Mondragon A, Chen L, Mcginty JA, French PM, Ferrer J, Thorens B, Hodson DJ, Rutter GA, Da Silva Xavier G. Selective disruption of Tcf7l2 in the pancreatic β cell impairs secretory function and lowers β cell mass. Hum Mol Genet 2014; 24:1390-9. [PMID: 25355422 PMCID: PMC4321446 DOI: 10.1093/hmg/ddu553] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Type 2 diabetes (T2D) is characterized by β cell dysfunction and loss. Single nucleotide polymorphisms in the T-cell factor 7-like 2 (TCF7L2) gene, associated with T2D by genome-wide association studies, lead to impaired β cell function. While deletion of the homologous murine Tcf7l2 gene throughout the developing pancreas leads to impaired glucose tolerance, deletion in the β cell in adult mice reportedly has more modest effects. To inactivate Tcf7l2 highly selectively in β cells from the earliest expression of the Ins1 gene (∼E11.5) we have therefore used a Cre recombinase introduced at the Ins1 locus. Tcfl2fl/fl::Ins1Cre mice display impaired oral and intraperitoneal glucose tolerance by 8 and 16 weeks, respectively, and defective responses to the GLP-1 analogue liraglutide at 8 weeks. Tcfl2fl/fl::Ins1Cre islets displayed defective glucose- and GLP-1-stimulated insulin secretion and the expression of both the Ins2 (∼20%) and Glp1r (∼40%) genes were significantly reduced. Glucose- and GLP-1-induced intracellular free Ca2+ increases, and connectivity between individual β cells, were both lowered by Tcf7l2 deletion in islets from mice maintained on a high (60%) fat diet. Finally, analysis by optical projection tomography revealed ∼30% decrease in β cell mass in pancreata from Tcfl2fl/fl::Ins1Cre mice. These data demonstrate that Tcf7l2 plays a cell autonomous role in the control of β cell function and mass, serving as an important regulator of gene expression and islet cell coordination. The possible relevance of these findings for the action of TCF7L2 polymorphisms associated with Type 2 diabetes in man is discussed.
Collapse
Affiliation(s)
- Ryan K Mitchell
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine
| | - Angeles Mondragon
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine
| | | | | | | | - Jorge Ferrer
- Section of Genetics and Medicine, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, UK
| | - Bernard Thorens
- Center for Integrative Genomics, Physiology Department, University of Lausanne, Genopode Building, CH-1015 Lausanne, Switzerland
| | - David J Hodson
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine
| | - Guy A Rutter
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine,
| | - Gabriela Da Silva Xavier
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine,
| |
Collapse
|
47
|
Mondragon A, Davidsson D, Kyriakoudi S, Bertling A, Gomes-Faria R, Cohen P, Rothery S, Chabosseau P, Rutter GA, da Silva Xavier G. Divergent effects of liraglutide, exendin-4, and sitagliptin on beta-cell mass and indicators of pancreatitis in a mouse model of hyperglycaemia. PLoS One 2014; 9:e104873. [PMID: 25119717 PMCID: PMC4132080 DOI: 10.1371/journal.pone.0104873] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Accepted: 06/23/2014] [Indexed: 01/29/2023] Open
Abstract
AIMS Glucagon-like peptide-1 (GLP-1) receptor agonists and dipeptidyl peptidase-4 (DPP4) inhibitors improve glucose tolerance by still incompletely understood mechanisms. Each class of antihyperglycemic drugs has also been proposed to increase pancreatitis risk. Here, we compare systematically the effects of two widely-used GLP-1 analogues, liraglutide and exendin-4, and the DPP4 inhibitor, sitagliptin, in the mouse. METHODS C57BL6 mice were maintained for 131 days on a normal diet (ND) or a diet comprising 60% fat (HFD) before measurements of fasting blood glucose and insulin, and intraperitoneal glucose tolerance. Beta- and alpha- cell volume, and Reg3b immunoreactivity, were measured by immunohistochemical analysis of pancreatic slices. RESULTS Whereas liraglutide (200 µg/kg) and exendin-4 (10 µg/kg) treatment reduced body weight and/or improved glucose tolerance, sitagliptin (10 mg/kg) was without effect on either parameter. Liraglutide caused a sharp reduction in beta-cell mass in both ND and HFD mice, whereas exendin-4 exerted no effect. By contrast, sitagliptin unmasked an action of high fat diet to increase beta-cell mass. Reg3B positive area was augmented by all three agents in normal chow-fed mice, whilst sitagliptin and exendin-4, but not liraglutide, affected this parameter in HFD animals. Correspondingly sitagliptin, but not the GLP-1 analogues, increased circulating amylase levels in ND and HFD mice. CONCLUSIONS Liraglutide improves glucose tolerance in the mouse whilst exerting relatively modest effects on pancreatitis risk. Conversely, exendin-4 and sitagliptin, at doses which exert, respectively, minor or no effects on metabolic parameters, lead to signs of pancreatitis.
Collapse
Affiliation(s)
- Angeles Mondragon
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Daniel Davidsson
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Styliana Kyriakoudi
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Annika Bertling
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Rosa Gomes-Faria
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Patrizia Cohen
- Imperial College Healthcare NHS Trust, Department of Pathology, St. Mary's Hospital, London, United Kingdom
| | | | - Pauline Chabosseau
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Guy A. Rutter
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Gabriela da Silva Xavier
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Faculty of Medicine, Imperial College London, London, United Kingdom
| |
Collapse
|
48
|
Shang SW, Yang JL, Huang F, Liu K, Liu BL. Modified Si-Miao-San ameliorates pancreatic B cell dysfunction by inhibition of reactive oxygen species-associated inflammation through AMP-kinase activation. Chin J Nat Med 2014; 12:351-60. [PMID: 24856758 DOI: 10.1016/s1875-5364(14)60043-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2013] [Indexed: 11/16/2022]
Abstract
AIM To observe the effect of modified Si-Miao-San (mSMS) on advanced glycation end products (AGEs)-induced pancreatic B cell dysfunction, as well as examining the underlying mechanisms. METHOD Pancreatic B cells (INS-1) were stimulated with advanced glycation end products (AGEs, 200 μg·mL(-1)) for 24 h to produce dysfunction in pancreatic B cells and the effects of mSMS observed on insulin secretion, NF-κB (p65) phosphorylation, reactive oxygen species (ROS) production, mitochondria membrane potential (Δψm), cell apoptosis, phosphorylation of AMP-kinase (AMPK), and caspase 3 activity. RESULTS The AGEs challenge resulted in increased basal insulin secretion, but decreased insulin secretion in response to high glucose, whereas this situation was reversed by mSMS treatment. AGEs stimulation induced NF-κB (p65) phosphorylation and reactive oxygen species (ROS) production, as well as Δψm collapse and cell apoptosis. mSMS inhibited ROS production and inhibited NF-κB activation by attenuating p65 phosphorylation. Meanwhile, AGEs-induced Δψm collapse and cell apoptosis were also reversed by mSMS treatment. Compound C, an inhibitor of AMP-Kinase (AMPK), abolished the beneficial effects of mSMS on the regulation of B cell function, indicating the involvement of AMPK. CONCLUSION mSMS ameliorated AGEs-induced B cell dysfunction by suppressing ROS-associated inflammation, and this action was related to its beneficial regulation of AMPK activity.
Collapse
Affiliation(s)
- Shu-Wan Shang
- State key laboratory of Natural Medicines, Department of Pharmacology of Chinese Materia Medica, China Pharmaceutical University, Nanjing 211198, China
| | - Jiang-Lin Yang
- State key laboratory of Natural Medicines, Department of Pharmacology of Chinese Materia Medica, China Pharmaceutical University, Nanjing 211198, China
| | - Fang Huang
- State key laboratory of Natural Medicines, Department of Pharmacology of Chinese Materia Medica, China Pharmaceutical University, Nanjing 211198, China
| | - Kang Liu
- State key laboratory of Natural Medicines, Department of Pharmacology of Chinese Materia Medica, China Pharmaceutical University, Nanjing 211198, China; Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing University of Chinese Medicines, Nanjing 210046, China
| | - Bao-Lin Liu
- State key laboratory of Natural Medicines, Department of Pharmacology of Chinese Materia Medica, China Pharmaceutical University, Nanjing 211198, China; Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing University of Chinese Medicines, Nanjing 210046, China.
| |
Collapse
|
49
|
Interactome analysis of AMP-activated protein kinase (AMPK)-α1 and -β1 in INS-1 pancreatic beta-cells by affinity purification-mass spectrometry. Sci Rep 2014; 4:4376. [PMID: 24625528 PMCID: PMC3953747 DOI: 10.1038/srep04376] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Accepted: 02/26/2014] [Indexed: 12/23/2022] Open
Abstract
The heterotrimeric enzyme AMP-activated protein kinase (AMPK) is a major metabolic factor that regulates the homeostasis of cellular energy. In particular, AMPK mediates the insulin resistance that is associated with type 2 diabetes. Generally, cellular processes require tight regulation of protein kinases, which is effected through their formation of complex with other proteins and substrates. Despite their critical function in regulation and pathogenesis, there are limited data on the interaction of protein kinases. To identify proteins that interact with AMPK, we performed large-scale affinity purification (AP)-mass spectrometry (MS) of the AMPK-α1 and -β1 subunits. Through a comprehensive analysis, using a combination of immunoprecipitaion and ion trap mass spectrometry, we identified 381 unique proteins in the AMPKα/β interactomes: 325 partners of AMPK-α1 and 243 for AMPK-β1. Further, we identified 196 novel protein-protein interactions with AMPK-α1 and AMPK-β1. Notably, in our bioinformatics analysis, the novel interaction partners mediated functions that are related to the regulation of actin organization. Specifically, several such proteins were linked to pancreatic beta-cell functions, including glucose-stimulated insulin secretion, beta-cell development, beta-cell differentiation, and cell-cell communication.
Collapse
|
50
|
Bernal-Mizrachi E, Kulkarni RN, Scott DK, Mauvais-Jarvis F, Stewart AF, Garcia-Ocaña A. Human β-cell proliferation and intracellular signaling part 2: still driving in the dark without a road map. Diabetes 2014; 63:819-31. [PMID: 24556859 PMCID: PMC3931400 DOI: 10.2337/db13-1146] [Citation(s) in RCA: 141] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Enhancing β-cell proliferation is a major goal for type 1 and type 2 diabetes research. Unraveling the network of β-cell intracellular signaling pathways that promote β-cell replication can provide the tools to address this important task. In a previous Perspectives in Diabetes article, we discussed what was known regarding several important intracellular signaling pathways in rodent β-cells, including the insulin receptor substrate/phosphatidylinositol-3 kinase/Akt (IRS-PI3K-Akt) pathways, glycogen synthase kinase-3 (GSK3) and mammalian target of rapamycin (mTOR) S6 kinase pathways, protein kinase Cζ (PKCζ) pathways, and their downstream cell-cycle molecular targets, and contrasted that ample knowledge to the small amount of complementary data on human β-cell intracellular signaling pathways. In this Perspectives, we summarize additional important information on signaling pathways activated by nutrients, such as glucose; growth factors, such as epidermal growth factor, platelet-derived growth factor, and Wnt; and hormones, such as leptin, estrogen, and progesterone, that are linked to rodent and human β-cell proliferation. With these two Perspectives, we attempt to construct a brief summary of knowledge for β-cell researchers on mitogenic signaling pathways and to emphasize how little is known regarding intracellular events linked to human β-cell replication. This is a critical aspect in the long-term goal of expanding human β-cells for the prevention and/or cure of type 1 and type 2 diabetes.
Collapse
Affiliation(s)
- Ernesto Bernal-Mizrachi
- Division of Metabolism, Endocrinology, and Diabetes, University of Michigan, and U.S. Department of Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, MI
- Corresponding authors: Ernesto Bernal-Mizrachi, , and Adolfo Garcia-Ocaña,
| | - Rohit N. Kulkarni
- Islet Cell Biology and Regenerative Medicine, Joslin Diabetes Center, Harvard Medical School, Boston, MA
- Department of Medicine, Harvard Medical School, Boston, MA
| | - Donald K. Scott
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Franck Mauvais-Jarvis
- Division of Endocrinology and Metabolism, Tulane University School of Medicine and Health Sciences Center, New Orleans, LA
| | - Andrew F. Stewart
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Adolfo Garcia-Ocaña
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, New York, NY
- Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY
- Corresponding authors: Ernesto Bernal-Mizrachi, , and Adolfo Garcia-Ocaña,
| |
Collapse
|