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Marhl M. What do stimulated beta cells have in common with cancer cells? Biosystems 2024; 242:105257. [PMID: 38876357 DOI: 10.1016/j.biosystems.2024.105257] [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: 03/26/2024] [Revised: 06/11/2024] [Accepted: 06/11/2024] [Indexed: 06/16/2024]
Abstract
This study investigates the metabolic parallels between stimulated pancreatic beta cells and cancer cells, focusing on glucose and glutamine metabolism. Addressing the significant public health challenges of Type 2 Diabetes (T2D) and cancer, we aim to deepen our understanding of the mechanisms driving insulin secretion and cellular proliferation. Our analysis of anaplerotic cycles and the role of NADPH in biosynthesis elucidates their vital functions in both processes. Additionally, we point out that both cell types share an antioxidative response mediated by the Nrf2 signaling pathway, glutathione synthesis, and UCP2 upregulation. Notably, UCP2 facilitates the transfer of C4 metabolites, enhancing reductive TCA cycle metabolism. Furthermore, we observe that hypoxic responses are transient in beta cells post-stimulation but persistent in cancer cells. By synthesizing these insights, the research may suggest novel therapeutic targets for T2D, highlighting the shared metabolic strategies of stimulated beta cells and cancer cells. This comparative analysis not only illuminates the metabolic complexity of these conditions but also emphasizes the crucial role of metabolic pathways in cell function and survival, offering fresh perspectives for tackling T2D and cancer challenges.
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Affiliation(s)
- Marko Marhl
- Faculty of Medicine, University of Maribor, Taborska ulica 8, 2000, Maribor, Slovenia; Faculty of Education, University of Maribor, Koroška cesta 160, 2000, Maribor, Slovenia; Faculty of Natural Sciences and Mathematics, University of Maribor, Koroška cesta 160, 2000, Maribor, Slovenia.
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2
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Sabadell-Basallote J, Astiarraga B, Castaño C, Ejarque M, Repollés-de-Dalmau M, Quesada I, Blanco J, Nuñez-Roa C, Rodríguez-Peña MM, Martínez L, De Jesus DF, Marroqui L, Bosch R, Montanya E, Sureda FX, Tura A, Mari A, Kulkarni RN, Vendrell J, Fernández-Veledo S. SUCNR1 regulates insulin secretion and glucose elevates the succinate response in people with prediabetes. J Clin Invest 2024; 134:e173214. [PMID: 38713514 PMCID: PMC11178533 DOI: 10.1172/jci173214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 04/26/2024] [Indexed: 05/09/2024] Open
Abstract
Pancreatic β-cell dysfunction is a key feature of type 2 diabetes, and novel regulators of insulin secretion are desirable. Here we report that the succinate receptor (SUCNR1) is expressed in β-cells and is up-regulated in hyperglycemic states in mice and humans. We found that succinate acts as a hormone-like metabolite and stimulates insulin secretion via a SUCNR1-Gq-PKC-dependent mechanism in human β-cells. Mice with β-cell-specific Sucnr1 deficiency exhibit impaired glucose tolerance and insulin secretion on a high-fat diet, indicating that SUCNR1 is essential for preserving insulin secretion in diet-induced insulin resistance. Patients with impaired glucose tolerance show an enhanced nutritional-related succinate response, which correlates with the potentiation of insulin secretion during intravenous glucose administration. These data demonstrate that the succinate/SUCNR1 axis is activated by high glucose and identify a GPCR-mediated amplifying pathway for insulin secretion relevant to the hyperinsulinemia of prediabetic states.
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Affiliation(s)
- Joan Sabadell-Basallote
- Unitat de Recerca, Hospital Universitari Joan XXIII, Insitut d'Investigació Sanitària Pere Virgili, Tarragona, Spain
| | - Brenno Astiarraga
- Unitat de Recerca, Hospital Universitari Joan XXIII, Insitut d'Investigació Sanitària Pere Virgili, Tarragona, Spain
| | - Carlos Castaño
- Unitat de Recerca, Hospital Universitari Joan XXIII, Institut d'Investigació Sanitària Pere Virgili, Tarragona, Spain
| | - Miriam Ejarque
- Unitat de Recerca, Hospital Universitari Joan XXIII, Insitut d'Investigació Sanitària Pere Virgili, Tarragona, Spain
| | - Maria Repollés-de-Dalmau
- Unitat de Recerca, Hospital Universitari Joan XXIII, Insitut d'Investigació Sanitària Pere Virgili, Tarragona, Spain
| | - Ivan Quesada
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas, Instituto de Salud Carlos III, ELCHE, Spain
| | - Jordi Blanco
- Departament de Medicina i Cirurgia, Universitat Rovira i Virgili, Reus, Spain
| | - Catalina Nuñez-Roa
- Unitat de Recerca, Hospital Universitari Joan XXIII, Institut d'Investigació Sanitària Pere Virgili, Tarragona, Spain
| | - M-Mar Rodríguez-Peña
- Unitat de Recerca, Hospital Universitari Joan XXIII, Institut d'Investigació Sanitària Pere Virgili, Tarragona, Spain
| | - Laia Martínez
- Unitat de Recerca, Hospital Universitari Joan XXIII, Institut d'Investigació Sanitària Pere Virgili, Tarragona, Spain
| | - Dario F De Jesus
- Section of Islet Cell and Regenerative Biology, Joslin Diabetes Center, Boston, United States of America
| | - Laura Marroqui
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas, Instituto de Salud Carlos III, ELCHE, Spain
| | - Ramon Bosch
- Unitat de Recerca, Hospital Universitari Joan XXIII, Insitut d'Investigació Sanitària Pere Virgili, Tarragona, Spain
| | - Eduard Montanya
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas, Instituto de Salud Carlos III, ELCHE, Spain
| | - Francesc X Sureda
- Section of Islet Cell and Regenerative Biology, Joslin Diabetes Center, Boston, United States of America
| | - Andrea Tura
- Institute of Neuroscience, National Research Council, Padova, Italy
| | - Andrea Mari
- Institute of Neuroscience, National Research Council, Padova, Italy
| | - Rohit N Kulkarni
- Section of Islet Cell and Regenerative Biology, Joslin Diabetes Center, Boston, United States of America
| | - Joan Vendrell
- Unitat de Recerca, Hospital Universitari Joan XXIII, Institut d'Investigació Sanitària Pere Virgili, Tarragona, Spain
| | - Sonia Fernández-Veledo
- Unitat de Recerca, Hospital Universitari Joan XXIII, Institut d'Investigació Sanitària Pere Virgili, Tarragona, Spain
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3
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Turbitt J, Moffett RC, Brennan L, Johnson PRV, Flatt PR, McClenaghan NH, Tarasov AI. Molecular determinants and intracellular targets of taurine signalling in pancreatic islet β-cells. Acta Physiol (Oxf) 2024; 240:e14101. [PMID: 38243723 DOI: 10.1111/apha.14101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 12/26/2023] [Accepted: 01/08/2024] [Indexed: 01/21/2024]
Abstract
AIM Despite its abundance in pancreatic islets of Langerhans and proven antihyperglycemic effects, the impact of the essential amino acid, taurine, on islet β-cell biology has not yet received due consideration, which prompted the current studies exploring the molecular selectivity of taurine import into β-cells and its acute and chronic intracellular interactions. METHODS The molecular aspects of taurine transport were probed by exposing the clonal pancreatic BRIN BD11 β-cells and primary mouse and human islets to a range of the homologs of the amino acid (assayed at 2-20 mM), using the hormone release and imaging of intracellular signals as surrogate read-outs. Known secretagogues were employed to profile the interaction of taurine with acute and chronic intracellular signals. RESULTS Taurine transporter TauT was expressed in the islet β-cells, with the transport of taurine and homologs having a weak sulfonate specificity but significant sensitivity to the molecular weight of the transporter. Taurine, hypotaurine, homotaurine, and β-alanine enhanced insulin secretion in a glucose-dependent manner, an action potentiated by cytosolic Ca2+ and cAMP. Acute and chronic β-cell insulinotropic effects of taurine were highly sensitive to co-agonism with GLP-1, forskolin, tolbutamide, and membrane depolarization, with an unanticipated indifference to the activation of PKC and CCK8 receptors. Pre-culturing with GLP-1 or KATP channel inhibitors sensitized or, respectively, desensitized β-cells to the acute taurine stimulus. CONCLUSION Together, these data demonstrate the pathways whereby taurine exhibits a range of beneficial effects on insulin secretion and β-cell function, consistent with the antidiabetic potential of its dietary low-dose supplementation.
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Affiliation(s)
- Julie Turbitt
- School of Biomedical Sciences, Ulster University, Coleraine, UK
| | | | - Lorraine Brennan
- UCD Institute of Food and Health, UCD School of Agriculture and Food Science, University College Dublin, Dublin 4, Republic of Ireland
- UCD Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Dublin 4, Republic of Ireland
| | - Paul R V Johnson
- Nuffield Department of Surgical Sciences, Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK
- Oxford Biomedical Research Centre (OxBRC), Oxford, UK
| | - Peter R Flatt
- School of Biomedical Sciences, Ulster University, Coleraine, UK
| | - Neville H McClenaghan
- School of Biomedical Sciences, Ulster University, Coleraine, UK
- Department of Life Sciences, Atlantic Technological University, Sligo, Republic of Ireland
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4
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Zhao M, Wang K, Lin R, Mu F, Cui J, Tao X, Weng Y, Wang J. Influence of glutamine metabolism on diabetes Development:A scientometric review. Heliyon 2024; 10:e25258. [PMID: 38375272 PMCID: PMC10875382 DOI: 10.1016/j.heliyon.2024.e25258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 01/22/2024] [Accepted: 01/23/2024] [Indexed: 02/21/2024] Open
Abstract
Objective "Metabolism affects function" is the consensus of researchers at present. It has potential clinical application value to study the effects of regulating glutamine (Gln) metabolism on diabetes physiology or pathology. Our research aimed to summarize the latest research progress, frontier hot topics and future development trends in this field from the perspective of scientometrics. Methods Relevant literatures and reviews were obtained from the Web of Science (WoS) between January 1, 2001 and May 31, 2022. An online analysis platform of bibliometrics, CiteSpace, and VOS viewer software were used to generate visual knowledge network graphs, including publication countries, institutions and authors partnership analysis, co-occurrence analysis, co-citation analysis, as well as citations and keywords burst detection to acquire research trends and hotspots. Results Our results showed that a total of 945 publications in the WoS database met the analysis requirements, with articles being the main type. The overall characteristics showed an increasing trend in the number of publications and citations. The United States was leading the way in this research and was a hub for aggregating collaborations across countries. Vanderbilt University delivered high-quality impact with the most published articles. DeBerardinis, RJ in this field was the most representative author and his main research contents were Gln metabolism and mitochondrial glutaminolysis. Significantly, there was a relative lack of collaboration between institutions and authors. In addition, "type 2 diabetes", "glutamine", "metabolism", "gene expression" and "metabolomics" were the keywords categories with high frequency in co-citation references and co-occurrence cluster keywords. Analysis of popular keywords burst detection showed that "branched chain", "oxidative phosphorylation", "kinase", "insulin sensitivity", "tca cycle", "magnetic resonance spectroscopy" and "flux analysis" were new research directions and emerging methods to explore the link between Gln metabolism and diabetes. Overall, exploring Gln metabolism showed a gradual upward trend in the field of diabetes. Conclusion This comprehensive scientometric study identified the general outlook for the field and provided valuable guidance for ongoing research. Strategies to regulate Gln metabolism hold promise as a novel target to treat diabetes, as well as integration and intersection of multidisciplinary provides cooperation strategies and technical guarantees for the development of this field.
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Affiliation(s)
- Meina Zhao
- Department of Pharmacy, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032 Shannxi Province, China
| | - Kaiyan Wang
- Department of Physiology and Pathophysiology, National Key Discipline of Cell Biology, Fourth Military Medical University, Xi'an, 710032 Shannxi Province, China
| | - Rui Lin
- Department of Pharmacy, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032 Shannxi Province, China
| | - Fei Mu
- Department of Pharmacy, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032 Shannxi Province, China
| | - Jia Cui
- Department of Pharmacy, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032 Shannxi Province, China
| | - Xingru Tao
- Department of Pharmacy, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032 Shannxi Province, China
| | - Yan Weng
- Department of Pharmacy, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032 Shannxi Province, China
| | - Jingwen Wang
- Department of Pharmacy, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032 Shannxi Province, China
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Rahul R, Stinchcombe AR, Joseph JW, Ingalls B. Kinetic modelling of β-cell metabolism reveals control points in the insulin-regulating pyruvate cycling pathways. IET Syst Biol 2023; 17:303-315. [PMID: 37938890 PMCID: PMC10725709 DOI: 10.1049/syb2.12077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 08/31/2023] [Accepted: 09/01/2023] [Indexed: 11/10/2023] Open
Abstract
Insulin, a key hormone in the regulation of glucose homoeostasis, is secreted by pancreatic β-cells in response to elevated glucose levels. Insulin is released in a biphasic manner in response to glucose metabolism in β-cells. The first phase of insulin secretion is triggered by an increase in the ATP:ADP ratio; the second phase occurs in response to both a rise in ATP:ADP and other key metabolic signals, including a rise in the NADPH:NADP+ ratio. Experimental evidence indicates that pyruvate-cycling pathways play an important role in the elevation of the NADPH:NADP+ ratio in response to glucose. The authors developed a kinetic model for the tricarboxylic acid cycle and pyruvate cycling pathways. The authors successfully validated the model against experimental observations and performed a sensitivity analysis to identify key regulatory interactions in the system. The model predicts that the dicarboxylate carrier and the pyruvate transporter are the most important regulators of pyruvate cycling and NADPH production. In contrast, the analysis showed that variation in the pyruvate carboxylase flux was compensated by a response in the activity of mitochondrial isocitrate dehydrogenase (ICDm ) resulting in minimal effect on overall pyruvate cycling flux. The model predictions suggest starting points for further experimental investigation, as well as potential drug targets for the treatment of type 2 diabetes.
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Affiliation(s)
- Rahul Rahul
- Department of Applied MathematicsUniversity of WaterlooWaterlooOntarioCanada
| | | | - Jamie W. Joseph
- School of PharmacyUniversity of WaterlooWaterlooOntarioCanada
| | - Brian Ingalls
- Department of Applied MathematicsUniversity of WaterlooWaterlooOntarioCanada
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Barsby T, Vähäkangas E, Ustinov J, Montaser H, Ibrahim H, Lithovius V, Kuuluvainen E, Chandra V, Saarimäki-Vire J, Katajisto P, Hietakangas V, Otonkoski T. Aberrant metabolite trafficking and fuel sensitivity in human pluripotent stem cell-derived islets. Cell Rep 2023; 42:112970. [PMID: 37556323 DOI: 10.1016/j.celrep.2023.112970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 06/09/2023] [Accepted: 07/26/2023] [Indexed: 08/11/2023] Open
Abstract
Pancreatic islets regulate blood glucose homeostasis through the controlled release of insulin; however, current metabolic models of glucose-sensitive insulin secretion are incomplete. A comprehensive understanding of islet metabolism is integral to studies of endocrine cell development as well as diabetic islet dysfunction. Human pluripotent stem cell-derived islets (SC-islets) are a developmentally relevant model of human islet function that have great potential in providing a cure for type 1 diabetes. Using multiple 13C-labeled metabolic fuels, we demonstrate that SC-islets show numerous divergent patterns of metabolite trafficking in proposed insulin release pathways compared with primary human islets but are still reliant on mitochondrial aerobic metabolism to derive function. Furthermore, reductive tricarboxylic acid cycle activity and glycolytic metabolite cycling occur in SC-islets, suggesting that non-canonical coupling factors are also present. In aggregate, we show that many facets of SC-islet metabolism overlap with those of primary islets, albeit with a retained immature signature.
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Affiliation(s)
- Tom Barsby
- Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
| | - Eliisa Vähäkangas
- Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Jarkko Ustinov
- Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Hossam Montaser
- Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Hazem Ibrahim
- Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Väinö Lithovius
- Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Emilia Kuuluvainen
- Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Vikash Chandra
- Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Jonna Saarimäki-Vire
- Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Pekka Katajisto
- Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Ville Hietakangas
- Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Timo Otonkoski
- Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland; Children's Hospital, Helsinki University Hospital and University of Helsinki, Helsinki, Finland.
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7
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Panten U, Brüning D, Rustenbeck I. Regulation of insulin secretion in mouse islets: metabolic amplification by alpha-ketoisocaproate coincides with rapid and sustained increase in acetyl-CoA content. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2023; 396:353-364. [PMID: 36355207 PMCID: PMC9832085 DOI: 10.1007/s00210-022-02290-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 09/05/2022] [Indexed: 11/12/2022]
Abstract
Glucose and alpha-ketoisocaproate, the keto acid analogue of leucine, stimulate insulin secretion in the absence of other exogenous fuels. Their mitochondrial metabolism in the beta-cell raises the cytosolic ATP/ADP ratio, thereby providing the triggering signal for the exocytosis of the insulin granules. However, additional amplifying signals are required for the full extent of insulin secretion stimulated by these fuels. While it is generally recognized that the amplifying signals are also derived from the mitochondrial metabolism, their exact nature is still unclear. The current study tests the hypothesis that the supply of cytosolic acetyl-CoA is a signal in the amplifying pathway. The contents of acetyl-CoA and acetyl-CoA plus CoA-SH were measured in isolated mouse islets. Insulin secretion was recorded in isolated perifused islets. In islets, the ATP-sensitive K+ channels of which were pharmacologically closed and which were preincubated without exogenous fuel, 10 mmol/L alpha-ketoisocaproate enhanced the acetyl-CoA content after 5 and 20 min incubations and decreased the acetyl-CoA plus CoA-SH within 5 min, but not after 20 min. In islets not exposed to drugs, the preincubation with 3 mmol/L glucose, a non-triggering concentration, elevated the acetyl-CoA content. This content was further increased after 5 min and 20 min incubations with 30 mmol/L glucose, concurrent with a strong increase in insulin secretion. Alpha-ketoisocaproate and glucose increase the supply of acetyl-CoA in the beta-cell cytosol during both phases of insulin secretion. Most likely, this increase provides a signal for the metabolic amplification.
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Affiliation(s)
- Uwe Panten
- Institute of Pharmacology, Toxicology and Clinical Pharmacy, Technische Universität Braunschweig, Mendelssohnstr. 1, 38106 Braunschweig, Germany
| | - Dennis Brüning
- Institute of Pharmacology, Toxicology and Clinical Pharmacy, Technische Universität Braunschweig, Mendelssohnstr. 1, 38106 Braunschweig, Germany
| | - Ingo Rustenbeck
- Institute of Pharmacology, Toxicology and Clinical Pharmacy, Technische Universität Braunschweig, Mendelssohnstr. 1, 38106 Braunschweig, Germany
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Stancill JS, Corbett JA. Hydrogen peroxide detoxification through the peroxiredoxin/thioredoxin antioxidant system: A look at the pancreatic β-cell oxidant defense. VITAMINS AND HORMONES 2022; 121:45-66. [PMID: 36707143 PMCID: PMC10058777 DOI: 10.1016/bs.vh.2022.11.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Reactive oxygen species (ROS), such as hydrogen peroxide, are formed when molecular oxygen obtains additional electrons, increasing its reactivity. While low concentrations of hydrogen peroxide are necessary for regulation of normal cellular signaling events, high concentrations can be toxic. To maintain this balance between beneficial and deleterious concentrations of hydrogen peroxide, cells utilize antioxidants. Our recent work supports a primary role for peroxiredoxin, thioredoxin, and thioredoxin reductase as the oxidant defense pathway used by insulin-producing pancreatic β-cells. These three players work in an antioxidant cycle based on disulfide exchange, with oxidized targets ultimately being reduced using electrons provided by NADPH. Peroxiredoxins also participate in hydrogen peroxide-based signaling through disulfide exchange with redox-regulated target proteins. This chapter will describe the catalytic mechanisms of thioredoxin, thioredoxin reductase, and peroxiredoxin and provide an in-depth look at the roles these enzymes play in antioxidant defense pathways of insulin-secreting β-cells. Finally, we will evaluate the physiological relevance of peroxiredoxin-mediated hydrogen peroxide signaling as a regulator of β-cell function.
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Affiliation(s)
- Jennifer S Stancill
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, United States
| | - John A Corbett
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, United States.
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9
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Brüning D, Morsi M, Früh E, Scherneck S, Rustenbeck I. Metabolic Regulation of Hormone Secretion in Beta-Cells and Alpha-Cells of Female Mice: Fundamental Differences. Endocrinology 2022; 163:6656576. [PMID: 35931024 DOI: 10.1210/endocr/bqac125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Indexed: 11/19/2022]
Abstract
It is unclear whether the secretion of glucagon is regulated by an alpha-cell-intrinsic mechanism and whether signal recognition by the mitochondrial metabolism plays a role in it. To measure changes of the cytosolic ATP/ADP ratio, single alpha-cells and beta-cells from NMRI mice were adenovirally transduced with the fluorescent indicator PercevalHR. The cytosolic Ca2+ concentration ([Ca2+]i) was measured by use of Fura2 and the mitochondrial membrane potential by use of TMRE. Perifused islets were used to measure the secretion of glucagon and insulin. At 5 mM glucose, the PercevalHR ratio in beta-cells was significantly lower than in alpha-cells. Lowering glucose to 1 mM decreased the ratio to 69% within 10 minutes in beta-cells, but only to 94% in alpha-cells. In this situation, 30 mM glucose, 10 mM alpha-ketoisocaproic acid, and 10 mM glutamine plus 10 mM BCH (a nonmetabolizable leucine analogue) markedly increased the PercevalHR ratio in beta-cells. In alpha-cells, only glucose was slightly effective. However, none of the nutrients increased the mitochondrial membrane potential in alpha-cells, whereas all did so in beta-cells. The kinetics of the PercevalHR increase were reflected by the kinetics of [Ca2+]i. increase in the beta-cells and insulin secretion. Glucagon secretion was markedly increased by washing out the nutrients with 1 mM glucose, but not by reducing glucose from 5 mM to 1 mM. This pattern was still recognizable when the insulin secretion was strongly inhibited by clonidine. It is concluded that mitochondrial energy metabolism is a signal generator in pancreatic beta-cells, but not in alpha-cells.
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Affiliation(s)
- Dennis Brüning
- Institute of Pharmacology, Toxicology and Clinical Pharmacy, Technische Universität Braunschweig, D 38106 Braunschweig, Germany
| | - Mai Morsi
- Institute of Pharmacology, Toxicology and Clinical Pharmacy, Technische Universität Braunschweig, D 38106 Braunschweig, Germany
- Department of Pharmacology, Faculty of Pharmacy, Assiut University, Assiut 71526, Egypt
| | - Eike Früh
- Institute of Pharmacology, Toxicology and Clinical Pharmacy, Technische Universität Braunschweig, D 38106 Braunschweig, Germany
| | - Stephan Scherneck
- Institute of Pharmacology, Toxicology and Clinical Pharmacy, Technische Universität Braunschweig, D 38106 Braunschweig, Germany
| | - Ingo Rustenbeck
- Institute of Pharmacology, Toxicology and Clinical Pharmacy, Technische Universität Braunschweig, D 38106 Braunschweig, Germany
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10
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Metabolic cycles and signals for insulin secretion. Cell Metab 2022; 34:947-968. [PMID: 35728586 PMCID: PMC9262871 DOI: 10.1016/j.cmet.2022.06.003] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Revised: 06/01/2022] [Accepted: 06/04/2022] [Indexed: 02/03/2023]
Abstract
In this review, we focus on recent developments in our understanding of nutrient-induced insulin secretion that challenge a key aspect of the "canonical" model, in which an oxidative phosphorylation-driven rise in ATP production closes KATP channels. We discuss the importance of intrinsic β cell metabolic oscillations; the phasic alignment of relevant metabolic cycles, shuttles, and shunts; and how their temporal and compartmental relationships align with the triggering phase or the secretory phase of pulsatile insulin secretion. Metabolic signaling components are assigned regulatory, effectory, and/or homeostatic roles vis-à-vis their contribution to glucose sensing, signal transmission, and resetting the system. Taken together, these functions provide a framework for understanding how allostery, anaplerosis, and oxidative metabolism are integrated into the oscillatory behavior of the secretory pathway. By incorporating these temporal as well as newly discovered spatial aspects of β cell metabolism, we propose a much-refined MitoCat-MitoOx model of the signaling process for the field to evaluate.
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11
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Stancill JS, Hansen PA, Mathison AJ, Schmidt EE, Corbett JA. Deletion of Thioredoxin Reductase Disrupts Redox Homeostasis and Impairs β-Cell Function. FUNCTION (OXFORD, ENGLAND) 2022; 3:zqac034. [PMID: 35873655 PMCID: PMC9301323 DOI: 10.1093/function/zqac034] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 06/17/2022] [Accepted: 06/27/2022] [Indexed: 01/07/2023]
Abstract
Reactive oxygen species (ROS) have been implicated as mediators of pancreatic β-cell damage. While β-cells are thought to be vulnerable to oxidative damage, we have shown, using inhibitors and acute depletion, that thioredoxin reductase, thioredoxin, and peroxiredoxins are the primary mediators of antioxidant defense in β-cells. However, the role of this antioxidant cycle in maintaining redox homeostasis and β-cell survival in vivo remains unclear. Here, we generated mice with a β-cell specific knockout of thioredoxin reductase 1 (Txnrd1fl/fl; Ins1Cre/+ , βKO). Despite blunted glucose-stimulated insulin secretion, knockout mice maintain normal whole-body glucose homeostasis. Unlike pancreatic islets with acute Txnrd1 inhibition, βKO islets do not demonstrate increased sensitivity to ROS. RNA-sequencing analysis revealed that Txnrd1-deficient β-cells have increased expression of nuclear factor erythroid 2-related factor 2 (Nrf2)-regulated genes, and altered expression of genes involved in heme and glutathione metabolism, suggesting an adaptive response. Txnrd1-deficient β-cells also have decreased expression of factors controlling β-cell function and identity which may explain the mild functional impairment. Together, these results suggest that Txnrd1-knockout β-cells compensate for loss of this essential antioxidant pathway by increasing expression of Nrf2-regulated antioxidant genes, allowing for protection from excess ROS at the expense of normal β-cell function and identity.
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Affiliation(s)
| | - Polly A Hansen
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, 53226, USA
| | - Angela J Mathison
- Genomic Sciences and Precision Medicine Center, Medical College of Wisconsin, Milwaukee, WI 53226, USA,Division of Research, Department of Surgery, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Edward E Schmidt
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MN 59717, USA,Redox Biology Laboratory, University of Veterinary Medicine, Budapest 1078, Hungary
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12
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Ding Q, Lu C, Hao Q, Zhang Q, Yang Y, Olsen RE, Ringo E, Ran C, Zhang Z, Zhou Z. Dietary Succinate Impacts the Nutritional Metabolism, Protein Succinylation and Gut Microbiota of Zebrafish. Front Nutr 2022; 9:894278. [PMID: 35685883 PMCID: PMC9171437 DOI: 10.3389/fnut.2022.894278] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 04/07/2022] [Indexed: 11/29/2022] Open
Abstract
Succinate is widely used in the food and feed industry as an acidulant, flavoring additive, and antimicrobial agent. This study investigated the effects of dietary succinate on growth, energy budget, nutritional metabolism, protein succinylation, and gut microbiota composition of zebrafish. Zebrafish were fed a control-check (0% succinate) or four succinate-supplemented diets (0.05, 0.10, 0.15, and 0.2%) for 4 weeks. The results showed that dietary succinate at the 0.15% additive amount (S0.15) can optimally promote weight gain and feed intake. Whole body protein, fat, and energy deposition increased in the S0.15 group. Fasting plasma glucose level decreased in fish fed the S0.15 diet, along with improved glucose tolerance. Lipid synthesis in the intestine, liver, and muscle increased with S0.15 feeding. Diet with 0.15% succinate inhibited intestinal gluconeogenesis but promoted hepatic gluconeogenesis. Glycogen synthesis increased in the liver and muscle of S0.15-fed fish. Glycolysis was increased in the muscle of S0.15-fed fish. In addition, 0.15% succinate-supplemented diet inhibited protein degradation in the intestine, liver, and muscle. Interestingly, different protein succinylation patterns in the intestine and liver were observed in fish fed the S0.15 diet. Intestinal proteins with increased succinylation levels were enriched in the tricarboxylic acid cycle while proteins with decreased succinylation levels were enriched in pathways related to fatty acid and amino acid degradation. Hepatic proteins with increased succinylation levels were enriched in oxidative phosphorylation while proteins with decreased succinylation levels were enriched in the processes of protein processing and transport in the endoplasmic reticulum. Finally, fish fed the S0.15 diet had a higher abundance of Proteobacteria but a lower abundance of Fusobacteria and Cetobacterium. In conclusion, dietary succinate could promote growth and feed intake, promote lipid anabolism, improve glucose homeostasis, and spare protein. The effects of succinate on nutritional metabolism are associated with alterations in the levels of metabolic intermediates, transcriptional regulation, and protein succinylation levels. However, hepatic fat accumulation and gut microbiota dysbiosis induced by dietary succinate suggest potential risks of succinate application as a feed additive for fish. This study would be beneficial in understanding the application of succinate as an aquatic feed additive.
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Affiliation(s)
- Qianwen Ding
- China-Norway Joint Lab on Fish Gastrointestinal Microbiota, Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing, China
- Norway-China Joint Lab on Fish Gastrointestinal Microbiota, Institute of Biology, Norwegian University of Science and Technology, Trondheim, Norway
| | - Chenyao Lu
- China-Norway Joint Lab on Fish Gastrointestinal Microbiota, Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Qiang Hao
- China-Norway Joint Lab on Fish Gastrointestinal Microbiota, Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Qingshuang Zhang
- China-Norway Joint Lab on Fish Gastrointestinal Microbiota, Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yalin Yang
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture and Rural Affairs, Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Rolf Erik Olsen
- Norway-China Joint Lab on Fish Gastrointestinal Microbiota, Institute of Biology, Norwegian University of Science and Technology, Trondheim, Norway
| | - Einar Ringo
- Norwegian College of Fishery Science, Faculty of Bioscience, Fisheries and Economics, UiT The Arctic University of Norway, Tromsø, Norway
| | - Chao Ran
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture and Rural Affairs, Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Zhen Zhang
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture and Rural Affairs, Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing, China
- *Correspondence: Zhen Zhang,
| | - Zhigang Zhou
- China-Norway Joint Lab on Fish Gastrointestinal Microbiota, Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing, China
- Zhigang Zhou,
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13
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Touitou F, Tortereau F, Bret L, Marty-Gasset N, Marcon D, Meynadier A. Evaluation of the Links between Lamb Feed Efficiency and Rumen and Plasma Metabolomic Data. Metabolites 2022; 12:metabo12040304. [PMID: 35448491 PMCID: PMC9029153 DOI: 10.3390/metabo12040304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 03/23/2022] [Accepted: 03/24/2022] [Indexed: 02/05/2023] Open
Abstract
Feed efficiency is one of the keystones that could help make animal production less costly and more environmentally friendly. Residual feed intake (RFI) is a widely used criterion to measure feed efficiency by regressing intake on the main energy sinks. We investigated rumen and plasma metabolomic data on Romane male lambs that had been genetically selected for either feed efficiency (line rfi−) or inefficiency (line rfi+). These investigations were conducted both during the growth phase under a 100% concentrate diet and later on under a mixed diet to identify differential metabolite expression and to link it to biological phenomena that could explain differences in feed efficiency. Nuclear magnetic resonance (NMR) data were analyzed using partial least squares discriminant analysis (PLS-DA), and correlations between metabolites’ relative concentrations were estimated to identify relationships between them. High levels of plasma citrate and malate were associated with genetically efficient animals, while high levels of amino acids such as L-threonine, L-serine, and L-leucine as well as beta-hydroxyisovalerate were associated with genetically inefficient animals under both diets. The two divergent lines could not be discriminated using rumen metabolites. Based on phenotypic residual feed intake (RFI), efficient and inefficient animals were discriminated using plasma metabolites determined under a 100% concentrate diet, but no discrimination was observed with plasma metabolites under a mixed diet or with rumen metabolites regardless of diet. Plasma amino acids, citrate, and malate were the most discriminant metabolites, suggesting that protein turnover and the mitochondrial production of energy could be the main phenomena that differ between efficient and inefficient Romane lambs.
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Affiliation(s)
- Florian Touitou
- GenPhySE, Université de Toulouse, INRAE, ENVT, F-31326 Castanet-Tolosan, France; (F.T.); (N.M.-G.); (A.M.)
- Correspondence:
| | - Flavie Tortereau
- GenPhySE, Université de Toulouse, INRAE, ENVT, F-31326 Castanet-Tolosan, France; (F.T.); (N.M.-G.); (A.M.)
| | - Lydie Bret
- Ecole Nationale Vétérinaire de Toulouse, F-31300 Toulouse, France;
| | - Nathalie Marty-Gasset
- GenPhySE, Université de Toulouse, INRAE, ENVT, F-31326 Castanet-Tolosan, France; (F.T.); (N.M.-G.); (A.M.)
| | - Didier Marcon
- INRAE, Experimental Unit P3R, F-18390 Osmoy, France;
| | - Annabelle Meynadier
- GenPhySE, Université de Toulouse, INRAE, ENVT, F-31326 Castanet-Tolosan, France; (F.T.); (N.M.-G.); (A.M.)
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14
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Francis EC, Kechris K, Cohen CC, Michelotti G, Dabelea D, Perng W. Metabolomic Profiles in Childhood and Adolescence Are Associated with Fetal Overnutrition. Metabolites 2022; 12:265. [PMID: 35323708 PMCID: PMC8952572 DOI: 10.3390/metabo12030265] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 03/07/2022] [Accepted: 03/16/2022] [Indexed: 02/01/2023] Open
Abstract
Fetal overnutrition predisposes offspring to increased metabolic risk. The current study used metabolomics to assess sustained differences in serum metabolites across childhood and adolescence among youth exposed to three typologies of fetal overnutrition: maternal obesity only, gestational diabetes mellitus (GDM) only, and obesity + GDM. We included youth exposed in utero to obesity only (BMI ≥ 30; n = 66), GDM only (n = 56), obesity + GDM (n = 25), or unexposed (n = 297), with untargeted metabolomics measured at ages 10 and 16 years. We used linear mixed models to identify metabolites across both time-points associated with exposure to any overnutrition, using a false-discovery-rate correction (FDR) <0.20. These metabolites were included in a principal component analysis (PCA) to generate profiles and assess metabolite profile differences with respect to overnutrition typology (adjusted for prenatal smoking, offspring age, sex, and race/ethnicity). Fetal overnutrition was associated with 52 metabolites. PCA yielded four factors accounting for 17−27% of the variance, depending on age of measurement. We observed differences in three factor patterns with respect to overnutrition typology: sphingomyelin-mannose (8−13% variance), skeletal muscle metabolism (6−10% variance), and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid (CMPF; 3−4% variance). The sphingomyelin-mannose factor score was higher among offspring exposed to obesity vs. GDM. Exposure to obesity + GDM (vs. GDM or obesity only) was associated with higher skeletal muscle metabolism and CMPF scores. Fetal overnutrition is associated with metabolic changes in the offspring, but differences between typologies of overnutrition account for a small amount of variation in the metabolome, suggesting there is likely greater pathophysiological overlap than difference.
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Affiliation(s)
- Ellen C. Francis
- Lifecourse Epidemiology of Adiposity and Diabetes (LEAD) Center, University of Colorado Denver Anschutz Medical Campus, Aurora, CO 80045, USA; (C.C.C.); (D.D.); (W.P.)
| | - Katerina Kechris
- Department of Biostatistics and Informatics, Colorado School of Public Health, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA;
| | - Catherine C. Cohen
- Lifecourse Epidemiology of Adiposity and Diabetes (LEAD) Center, University of Colorado Denver Anschutz Medical Campus, Aurora, CO 80045, USA; (C.C.C.); (D.D.); (W.P.)
- Department of Pediatrics, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | | | - Dana Dabelea
- Lifecourse Epidemiology of Adiposity and Diabetes (LEAD) Center, University of Colorado Denver Anschutz Medical Campus, Aurora, CO 80045, USA; (C.C.C.); (D.D.); (W.P.)
- Department of Pediatrics, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Department of Epidemiology, Colorado School of Public Health, University of Colorado Denver Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Wei Perng
- Lifecourse Epidemiology of Adiposity and Diabetes (LEAD) Center, University of Colorado Denver Anschutz Medical Campus, Aurora, CO 80045, USA; (C.C.C.); (D.D.); (W.P.)
- Department of Epidemiology, Colorado School of Public Health, University of Colorado Denver Anschutz Medical Campus, Aurora, CO 80045, USA
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15
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Hamilton JS, Klett EL. Linoleic acid and the regulation of glucose homeostasis: A review of the evidence. Prostaglandins Leukot Essent Fatty Acids 2021; 175:102366. [PMID: 34763302 PMCID: PMC8691379 DOI: 10.1016/j.plefa.2021.102366] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 10/27/2021] [Accepted: 10/27/2021] [Indexed: 12/14/2022]
Abstract
The consumption of linoleic acid (LA, ω-6 18:2), the most common ω-6 polyunsaturated fatty acid (PUFA) in the Modern Western diet (MWD), has significantly increased over the last century in tandem with unprecedented incidence of chronic metabolic diseases like obesity and type 2 diabetes mellitus (T2DM). Although an essential fatty acid for health, LA was a very rare fatty acid in the diet of humans during their evolution. While the intake of other dietary macronutrients (carbohydrates like fructose) has also risen, diets rich in ω-6 PUFAs have been promoted in an effort to reduce cardiovascular disease despite unclear evidence as to how increased dietary LA consumption could promote a proinflammatory state and affect glucose metabolism. Current evidence suggests that sex, genetics, environmental factors, and disease status can differentially modulate how LA influences insulin sensitivity and peripheral glucose uptake as well as insulin secretion and pancreatic beta-cell function. Therefore, the aim of this review will be to summarize recent additions to our knowledge to refine the unique physiological and pathophysiological roles of LA in the regulation of glucose homeostasis.
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Affiliation(s)
- Jakob S Hamilton
- Department of Nutrition, University of North Carolina School of Public Health, Chapel Hill, North Carolina, United States of America
| | - Eric L Klett
- Department of Medicine, Division of Endocrinology, University of North Carolina School of Medicine, Chapel Hill, NC, United States of America; Department of Nutrition, University of North Carolina School of Public Health, Chapel Hill, North Carolina, United States of America.
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16
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Close AF, Chae H, Jonas JC. The lack of functional nicotinamide nucleotide transhydrogenase only moderately contributes to the impairment of glucose tolerance and glucose-stimulated insulin secretion in C57BL/6J vs C57BL/6N mice. Diabetologia 2021; 64:2550-2561. [PMID: 34448880 DOI: 10.1007/s00125-021-05548-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 05/26/2021] [Indexed: 12/31/2022]
Abstract
AIMS/HYPOTHESIS Nicotinamide nucleotide transhydrogenase (NNT) is involved in mitochondrial NADPH production and its spontaneous inactivating mutation (NntTr [Tr, truncated]) is usually considered to be the main cause of the lower glucose tolerance of C57BL/6J vs C57BL/6N mice. However, the impact of this mutation on glucose tolerance remains disputed. Here, we singled out the impact of NntTr from that of other genetic variants between C57BL/6J and C57BL/6N mice on mitochondrial glutathione redox state (EGSH), glucose-stimulated insulin secretion (GSIS) and glucose tolerance. METHODS Male and female N5BL/6J mice that express wild-type Nnt (NntWT) or NntTr (N5-WT and N5-Tr mice) on the C57BL/6J genetic background were obtained by crossing N5BL/6J NntWT/Tr heterozygous mice. C57BL/6J and C57BL/6N mice were from Janvier Labs. The Nnt genotype was confirmed by PCR and the genetic background by whole genome sequencing of one mouse of each type. Glucose tolerance was assessed by IPGTT, ITT and fasting/refeeding tests. Stimulus-secretion coupling events and GSIS were measured in isolated pancreatic islets. Cytosolic and mitochondrial EGSH were measured using the fluorescent redox probe GRX1-roGFP2 (glutaredoxin 1 fused to redox-sensitive enhanced GFP). RESULTS The Nnt genotype and genetic background of each type of mouse were confirmed. As reported previously in C57BL/6N vs C57BL/6J islets, the glucose regulation of mitochondrial (but not cytosolic) EGSH and of NAD(P)H autofluorescence was markedly improved in N5-WT vs N5-Tr islets, confirming the role of NNT in mitochondrial redox regulation. However, ex vivo GSIS was only 1.2-1.4-times higher in N5-WT vs N5-Tr islets, while it was 2.4-times larger in C57BL/6N vs N5-WT islets, questioning the role of NNT in GSIS. In vivo, the ITT results did not differ between N5-WT and N5-Tr or C57BL/6N mice. However, the glucose excursion during an IPGTT was only 15-20% lower in female N5-WT mice than in N5-Tr and C57BL/6J mice and remained 3.5-times larger than in female C57BL/6N mice. Similar observations were made during a fasting/refeeding test. A slightly larger (~30%) impact of NNT on glucose tolerance was found in males. CONCLUSIONS/INTERPRETATION Although our results confirm the importance of NNT in the regulation of mitochondrial redox state by glucose, they markedly downsize the role of NNT in the alteration of GSIS and glucose tolerance in C57BL/6J vs C57BL/6N mice. Therefore, documenting an NntWT genotype in C57BL/6 mice does not provide proof that their glucose tolerance is as good as in C57BL/6N mice.
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Affiliation(s)
- Anne-Françoise Close
- Secteur des sciences de la santé, Institut de recherche expérimentale et clinique, Pôle d'endocrinologie, diabète et nutrition, Université catholique de Louvain, Brussels, Belgium
| | - Heeyoung Chae
- Secteur des sciences de la santé, Institut de recherche expérimentale et clinique, Pôle d'endocrinologie, diabète et nutrition, Université catholique de Louvain, Brussels, Belgium
| | - Jean-Christophe Jonas
- Secteur des sciences de la santé, Institut de recherche expérimentale et clinique, Pôle d'endocrinologie, diabète et nutrition, Université catholique de Louvain, Brussels, Belgium.
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17
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Fernández-Veledo S, Ceperuelo-Mallafré V, Vendrell J. Rethinking succinate: an unexpected hormone-like metabolite in energy homeostasis. Trends Endocrinol Metab 2021; 32:680-692. [PMID: 34301438 DOI: 10.1016/j.tem.2021.06.003] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 06/15/2021] [Accepted: 06/16/2021] [Indexed: 02/07/2023]
Abstract
There has been an explosion of interest in the signaling capacity of energy metabolites. A prime example is the Krebs cycle substrate succinate, an archetypal respiratory substrate with functions beyond energy production as an intracellular and extracellular signaling molecule. Long associated with inflammation, emerging evidence supports a key role for succinate in metabolic processes relating to energy management. As the natural ligand for SUCNR1, a G protein-coupled receptor, succinate is akin to hormones and likely functions as a reporter of metabolism and stress. In this review, we reconcile new and old observations to outline a regulatory role for succinate in metabolic homeostasis. We highlight the importance of the succinate-SUCNR1 axis in metabolic diseases as an integrator of macrophage immune response, and we discuss new metabolic functions recently ascribed to succinate in specific tissues. Because circulating succinate has emerged as a promising biomarker in chronic metabolic diseases, a better understanding of the physiopathological role of the succinate-SUCNR1 axis in metabolism might open new avenues for clinical use in patients with obesity or diabetes.
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Affiliation(s)
- Sonia Fernández-Veledo
- Department of Endocrinology and Nutrition and Research Unit, University Hospital of Tarragona Joan XXIII, Institut d'Investigació Sanitària Pere Virgili (IISPV), Tarragona, Spain; CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, Madrid, Spain.
| | - Victòria Ceperuelo-Mallafré
- Department of Endocrinology and Nutrition and Research Unit, University Hospital of Tarragona Joan XXIII, Institut d'Investigació Sanitària Pere Virgili (IISPV), Tarragona, Spain; CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, Madrid, Spain; Department of Medicine and Surgery, University Rovira I Virgili, Tarragona, Spain
| | - Joan Vendrell
- Department of Endocrinology and Nutrition and Research Unit, University Hospital of Tarragona Joan XXIII, Institut d'Investigació Sanitària Pere Virgili (IISPV), Tarragona, Spain; CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, Madrid, Spain; Department of Medicine and Surgery, University Rovira I Virgili, Tarragona, Spain
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18
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MacDonald MJ, Ansari IUH, Longacre MJ, Stoker SW. Metformin's Therapeutic Efficacy in the Treatment of Diabetes Does Not Involve Inhibition of Mitochondrial Glycerol Phosphate Dehydrogenase. Diabetes 2021; 70:1575-1580. [PMID: 33849997 DOI: 10.2337/db20-1143] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 04/08/2021] [Indexed: 11/13/2022]
Abstract
Mitochondrial glycerol phosphate dehydrogenase (mGPD) is the rate-limiting enzyme of the glycerol phosphate redox shuttle. It was recently claimed that metformin, a first-line drug used for the treatment of type 2 diabetes, inhibits liver mGPD 30-50%, suppressing gluconeogenesis through a redox mechanism. Various factors cast doubt on this idea. Total-body knockout of mGPD in mice has adverse effects in several tissues where the mGPD level is high but has little or no effect in liver, where the mGPD level is the lowest of 10 tissues. Metformin has beneficial effects in humans in tissues with high levels of mGPD, such as pancreatic β-cells, where the mGPD level is much higher than that in liver. Insulin secretion in mGPD knockout mouse β-cells is normal because, like liver, β-cells possess the malate aspartate redox shuttle whose redox action is redundant to the glycerol phosphate shuttle. For these and other reasons, we used four different enzyme assays to reassess whether metformin inhibited mGPD. Metformin did not inhibit mGPD in homogenates or mitochondria from insulin cells or liver cells. If metformin actually inhibited mGPD, adverse effects in tissues where the level of mGPD is much higher than that in the liver could prevent the use of metformin as a diabetes medicine.
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Affiliation(s)
| | - Israr-Ul H Ansari
- University of Wisconsin School of Medicine and Public Health, Madison, WI
| | - Melissa J Longacre
- University of Wisconsin School of Medicine and Public Health, Madison, WI
| | - Scott W Stoker
- University of Wisconsin School of Medicine and Public Health, Madison, WI
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19
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Prochownik EV, Wang H. The Metabolic Fates of Pyruvate in Normal and Neoplastic Cells. Cells 2021; 10:cells10040762. [PMID: 33808495 PMCID: PMC8066905 DOI: 10.3390/cells10040762] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 03/23/2021] [Accepted: 03/28/2021] [Indexed: 02/06/2023] Open
Abstract
Pyruvate occupies a central metabolic node by virtue of its position at the crossroads of glycolysis and the tricarboxylic acid (TCA) cycle and its production and fate being governed by numerous cell-intrinsic and extrinsic factors. The former includes the cell’s type, redox state, ATP content, metabolic requirements and the activities of other metabolic pathways. The latter include the extracellular oxygen concentration, pH and nutrient levels, which are in turn governed by the vascular supply. Within this context, we discuss the six pathways that influence pyruvate content and utilization: 1. The lactate dehydrogenase pathway that either converts excess pyruvate to lactate or that regenerates pyruvate from lactate for use as a fuel or biosynthetic substrate; 2. The alanine pathway that generates alanine and other amino acids; 3. The pyruvate dehydrogenase complex pathway that provides acetyl-CoA, the TCA cycle’s initial substrate; 4. The pyruvate carboxylase reaction that anaplerotically supplies oxaloacetate; 5. The malic enzyme pathway that also links glycolysis and the TCA cycle and generates NADPH to support lipid bio-synthesis; and 6. The acetate bio-synthetic pathway that converts pyruvate directly to acetate. The review discusses the mechanisms controlling these pathways, how they cross-talk and how they cooperate and are regulated to maximize growth and achieve metabolic and energetic harmony.
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Affiliation(s)
- Edward V. Prochownik
- Division of Hematology/Oncology, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA 15224, USA;
- The Department of Microbiology and Molecular Genetics, UPMC, Pittsburgh, PA 15213, USA
- The Hillman Cancer Center, UPMC, Pittsburgh, PA 15213, USA
- The Pittsburgh Liver Research Center, Pittsburgh, PA 15260, USA
- Correspondence: ; Tel.: +1-(412)-692-6795
| | - Huabo Wang
- Division of Hematology/Oncology, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA 15224, USA;
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20
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Campbell JE, Newgard CB. Mechanisms controlling pancreatic islet cell function in insulin secretion. Nat Rev Mol Cell Biol 2021; 22:142-158. [PMID: 33398164 DOI: 10.1038/s41580-020-00317-7] [Citation(s) in RCA: 251] [Impact Index Per Article: 83.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/19/2020] [Indexed: 02/07/2023]
Abstract
Metabolic homeostasis in mammals is tightly regulated by the complementary actions of insulin and glucagon. The secretion of these hormones from pancreatic β-cells and α-cells, respectively, is controlled by metabolic, endocrine, and paracrine regulatory mechanisms and is essential for the control of blood levels of glucose. The deregulation of these mechanisms leads to various pathologies, most notably type 2 diabetes, which is driven by the combined lesions of impaired insulin action and a loss of the normal insulin secretion response to glucose. Glucose stimulates insulin secretion from β-cells in a bi-modal fashion, and new insights about the underlying mechanisms, particularly relating to the second or amplifying phase of this secretory response, have been recently gained. Other recent work highlights the importance of α-cell-produced proglucagon-derived peptides, incretin hormones from the gastrointestinal tract and other dietary components, including certain amino acids and fatty acids, in priming and potentiation of the β-cell glucose response. These advances provide a new perspective for the understanding of the β-cell failure that triggers type 2 diabetes.
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Affiliation(s)
- Jonathan E Campbell
- Sarah W. Stedman Nutrition and Metabolism Center and Duke Molecular Physiology Institute, Duke University Medical Center, Durham, NC, USA.,Department of Medicine, Endocrinology and Metabolism Division, Duke University Medical Center, Durham, NC, USA.,Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC, USA
| | - Christopher B Newgard
- Sarah W. Stedman Nutrition and Metabolism Center and Duke Molecular Physiology Institute, Duke University Medical Center, Durham, NC, USA. .,Department of Medicine, Endocrinology and Metabolism Division, Duke University Medical Center, Durham, NC, USA. .,Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC, USA.
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21
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Stancill JS, Corbett JA. The Role of Thioredoxin/Peroxiredoxin in the β-Cell Defense Against Oxidative Damage. Front Endocrinol (Lausanne) 2021; 12:718235. [PMID: 34557160 PMCID: PMC8453158 DOI: 10.3389/fendo.2021.718235] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 08/19/2021] [Indexed: 02/02/2023] Open
Abstract
Oxidative stress is hypothesized to play a role in pancreatic β-cell damage, potentially contributing to β-cell dysfunction and death in both type 1 and type 2 diabetes. Oxidative stress arises when naturally occurring reactive oxygen species (ROS) are produced at levels that overwhelm the antioxidant capacity of the cell. ROS, including superoxide and hydrogen peroxide, are primarily produced by electron leak during mitochondrial oxidative metabolism. Additionally, peroxynitrite, an oxidant generated by the reaction of superoxide and nitric oxide, may also cause β-cell damage during autoimmune destruction of these cells. β-cells are thought to be susceptible to oxidative damage based on reports that they express low levels of antioxidant enzymes compared to other tissues. Furthermore, markers of oxidative damage are observed in islets from diabetic rodent models and human patients. However, recent studies have demonstrated high expression of various isoforms of peroxiredoxins, thioredoxin, and thioredoxin reductase in β-cells and have provided experimental evidence supporting a role for these enzymes in promoting β-cell function and survival in response to a variety of oxidative stressors. This mini-review will focus on the mechanism by which thioredoxins and peroxiredoxins detoxify ROS and on the protective roles of these enzymes in β-cells. Additionally, we speculate about the role of this antioxidant system in promoting insulin secretion.
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22
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Lewandowski SL, Cardone RL, Foster HR, Ho T, Potapenko E, Poudel C, VanDeusen HR, Sdao SM, Alves TC, Zhao X, Capozzi ME, de Souza AH, Jahan I, Thomas CJ, Nunemaker CS, Davis DB, Campbell JE, Kibbey RG, Merrins MJ. Pyruvate Kinase Controls Signal Strength in the Insulin Secretory Pathway. Cell Metab 2020; 32:736-750.e5. [PMID: 33147484 PMCID: PMC7685238 DOI: 10.1016/j.cmet.2020.10.007] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 06/30/2020] [Accepted: 10/09/2020] [Indexed: 12/14/2022]
Abstract
Pancreatic β cells couple nutrient metabolism with appropriate insulin secretion. Here, we show that pyruvate kinase (PK), which converts ADP and phosphoenolpyruvate (PEP) into ATP and pyruvate, underlies β cell sensing of both glycolytic and mitochondrial fuels. Plasma membrane-localized PK is sufficient to close KATP channels and initiate calcium influx. Small-molecule PK activators increase the frequency of ATP/ADP and calcium oscillations and potently amplify insulin secretion. PK restricts respiration by cyclically depriving mitochondria of ADP, which accelerates PEP cycling until membrane depolarization restores ADP and oxidative phosphorylation. Our findings support a compartmentalized model of β cell metabolism in which PK locally generates the ATP/ADP required for insulin secretion. Oscillatory PK activity allows mitochondria to perform synthetic and oxidative functions without any net impact on glucose oxidation. These findings suggest a potential therapeutic route for diabetes based on PK activation that would not be predicted by the current consensus single-state model of β cell function.
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Affiliation(s)
- Sophie L Lewandowski
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Rebecca L Cardone
- Department of Internal Medicine, Yale University, New Haven, CT 06520, USA
| | - Hannah R Foster
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Thuong Ho
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Evgeniy Potapenko
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Chetan Poudel
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Halena R VanDeusen
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Sophia M Sdao
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Tiago C Alves
- Department of Internal Medicine, Yale University, New Haven, CT 06520, USA
| | - Xiaojian Zhao
- Department of Internal Medicine, Yale University, New Haven, CT 06520, USA
| | - Megan E Capozzi
- Duke Molecular Physiology Institute, Duke University, Durham, NC 27701, USA
| | - Arnaldo H de Souza
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Ishrat Jahan
- Department of Biomedical Sciences, Ohio University, Athens, OH 45701, USA
| | - Craig J Thomas
- National Center for Advancing Translational Sciences, Rockville, MD 20850, USA
| | - Craig S Nunemaker
- Department of Biomedical Sciences, Ohio University, Athens, OH 45701, USA
| | - Dawn Belt Davis
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Wisconsin-Madison, Madison, WI 53705, USA
| | | | - Richard G Kibbey
- Department of Internal Medicine, Yale University, New Haven, CT 06520, USA; Department of Cellular & Molecular Physiology, Yale University, New Haven, CT 06520, USA.
| | - Matthew J Merrins
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Wisconsin-Madison, Madison, WI 53705, USA; William S. Middleton Memorial Veterans Hospital, Madison, WI 53705, USA.
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23
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Abulizi A, Cardone RL, Stark R, Lewandowski SL, Zhao X, Hillion J, Ma L, Sehgal R, Alves TC, Thomas C, Kung C, Wang B, Siebel S, Andrews ZB, Mason GF, Rinehart J, Merrins MJ, Kibbey RG. Multi-Tissue Acceleration of the Mitochondrial Phosphoenolpyruvate Cycle Improves Whole-Body Metabolic Health. Cell Metab 2020; 32:751-766.e11. [PMID: 33147485 PMCID: PMC7679013 DOI: 10.1016/j.cmet.2020.10.006] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 06/30/2020] [Accepted: 10/09/2020] [Indexed: 12/25/2022]
Abstract
The mitochondrial GTP (mtGTP)-dependent phosphoenolpyruvate (PEP) cycle couples mitochondrial PEPCK (PCK2) to pyruvate kinase (PK) in the liver and pancreatic islets to regulate glucose homeostasis. Here, small molecule PK activators accelerated the PEP cycle to improve islet function, as well as metabolic homeostasis, in preclinical rodent models of diabetes. In contrast, treatment with a PK activator did not improve insulin secretion in pck2-/- mice. Unlike other clinical secretagogues, PK activation enhanced insulin secretion but also had higher insulin content and markers of differentiation. In addition to improving insulin secretion, acute PK activation short-circuited gluconeogenesis to reduce endogenous glucose production while accelerating red blood cell glucose turnover. Four-week delivery of a PK activator in vivo remodeled PK phosphorylation, reduced liver fat, and improved hepatic and peripheral insulin sensitivity in HFD-fed rats. These data provide a preclinical rationale for PK activation to accelerate the PEP cycle to improve metabolic homeostasis and insulin sensitivity.
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Affiliation(s)
| | - Rebecca L Cardone
- Department of Internal Medicine, Yale University, New Haven, CT 06520, USA
| | - Romana Stark
- Department of Physiology, Monash University, Melbourne, VIC 3800, Australia
| | - Sophie L Lewandowski
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, and Department of Biomolecular Chemistry, University of Wisconsin-Madison, and William S. Middleton Memorial Veterans Hospital, Madison, WI, USA
| | - Xiaojian Zhao
- Department of Internal Medicine, Yale University, New Haven, CT 06520, USA
| | - Joelle Hillion
- Department of Internal Medicine, Yale University, New Haven, CT 06520, USA
| | - Lingjun Ma
- Department of Internal Medicine, Yale University, New Haven, CT 06520, USA
| | - Raghav Sehgal
- Department of Internal Medicine, Yale University, New Haven, CT 06520, USA
| | - Tiago C Alves
- Department of Internal Medicine, Yale University, New Haven, CT 06520, USA
| | - Craig Thomas
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, and Lymphoid Malignancies Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | | | - Bei Wang
- Department of Internal Medicine, Yale University, New Haven, CT 06520, USA
| | - Stephan Siebel
- Department of Internal Medicine, Yale University, New Haven, CT 06520, USA
| | - Zane B Andrews
- Department of Physiology, Monash University, Melbourne, VIC 3800, Australia
| | - Graeme F Mason
- Department of Diagnostic Radiology and Psychiatry, Yale University, New Haven, CT 06520, USA
| | - Jesse Rinehart
- Department of Cellular & Molecular Physiology, Yale University, New Haven, CT 06520, USA
| | - Matthew J Merrins
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, and Department of Biomolecular Chemistry, University of Wisconsin-Madison, and William S. Middleton Memorial Veterans Hospital, Madison, WI, USA
| | - Richard G Kibbey
- Department of Internal Medicine, Yale University, New Haven, CT 06520, USA; Department of Cellular & Molecular Physiology, Yale University, New Haven, CT 06520, USA.
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24
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Prasun P. Role of mitochondria in pathogenesis of type 2 diabetes mellitus. J Diabetes Metab Disord 2020; 19:2017-2022. [PMID: 33520874 DOI: 10.1007/s40200-020-00679-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 10/28/2020] [Indexed: 01/09/2023]
Abstract
Type 2 diabetes mellitus (T2DM) is global health problem. An estimated 425 million people in the world had diabetes in 2017. It is a major cause of morbidity and mortality worldwide. Although, pathogenesis of T2DM and its complications have been focus of medical research for long, much remains to be learned. A better understanding of molecular pathogenesis is essential for more effective preventive and therapeutic interventions. Role of mitochondria in pathogenesis of metabolic problems such as obesity, metabolic syndrome, and T2DM is the focus of many recent research studies. Mitochondrial dysfunction contributes to the oxidative stress and systemic inflammation leading to insulin resistance (IR). Mitochondria are also essential for pancreatic beta cell insulin secretion. Hence, mitochondria are important players in the pathogenesis of T2DM. In this article, pathogenesis of T2DM is examined from a mitochondrial perspective.
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Affiliation(s)
- Pankaj Prasun
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place - Box 1497, New York, NY 10029 USA
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25
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Abstract
Anaplerosis and the associated mitochondrial metabolite transporters generate unique cytosolic metabolic signaling molecules that can regulate insulin release from pancreatic β-cells. It has been shown that mitochondrial metabolites, transported by the citrate carrier (CIC), dicarboxylate carrier (DIC), oxoglutarate carrier (OGC), and mitochondrial pyruvate carrier (MPC) play a vital role in the regulation of glucose-stimulated insulin secretion (GSIS). Metabolomic studies on static and biphasic insulin secretion, suggests that several anaplerotic derived metabolites, including α-ketoglutarate (αKG), are strongly associated with nutrient regulated insulin secretion. Support for a role of αKG in the regulation of insulin secretion comes from studies looking at αKG dependent enzymes, including hypoxia-inducible factor-prolyl hydroxylases (PHDs) in clonal β-cells, and rodent and human islets. This review will focus on the possible link between defective anaplerotic-derived αKG, PHDs, and the development of type 2 diabetes (T2D).
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Affiliation(s)
- M. Hoang
- School of Pharmacy, University of Waterloo, Kitchener, Ontario, Canada
| | - J. W. Joseph
- School of Pharmacy, University of Waterloo, Kitchener, Ontario, Canada
- CONTACT J. W. Joseph School of Pharmacy, University of Waterloo, Kitchener, ONN2G1C5, Canada
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26
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Wang C, Liu Y, Zhu Y, Kong C. Functions of mammalian SIRT4 in cellular metabolism and research progress in human cancer. Oncol Lett 2020; 20:11. [PMID: 32774484 PMCID: PMC7405384 DOI: 10.3892/ol.2020.11872] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 05/18/2020] [Indexed: 12/11/2022] Open
Abstract
Sirtuins are mammalian homologs of yeast silent information regulator two (SIRT) and are a highly conserved family of proteins, which act as nicotinamide adenine dinucleotide (NAD+)-dependent histone deacetylases. The seven sirtuins (SIRT1-7) share a conserved catalytic core domain; however, they have different enzyme activities, biological functions, and subcellular localizations. Among them, mitochondrial SIRT4 possesses ADP-ribosyltransferase, NAD+-dependent deacetylase, lipoamidase, and long-chain deacylase activities and can modulate the function of substrate proteins via ADP-ribosylation, delipoylation, deacetylation and long-chain deacylation. SIRT4 has been shown to play a crucial role in insulin secretion, fatty acid oxidation, amino acid metabolism, ATP homeostasis, apoptosis, neurodegeneration, and cardiovascular diseases. In addition, recent studies have demonstrated that SIRT4 acts as a tumor suppressor. Here, the present review summarizes the enzymatic activities and biological functions of SIRT4, as well as its roles in cellular metabolism and human cancer, which are described in the current literature.
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Affiliation(s)
- Changming Wang
- Department of Urology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China.,Department of Urological Laboratory, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Yan Liu
- Department of Pharmaceutical Toxicology, School of Pharmacy, China Medical University, Shenyang, Liaoning 110122, P.R. China
| | - Yuyan Zhu
- Department of Urology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China.,Department of Urological Laboratory, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Chuize Kong
- Department of Urology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China.,Department of Urological Laboratory, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
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27
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Mnatsakanyan N, Jonas EA. ATP synthase c-subunit ring as the channel of mitochondrial permeability transition: Regulator of metabolism in development and degeneration. J Mol Cell Cardiol 2020; 144:109-118. [PMID: 32461058 PMCID: PMC7877492 DOI: 10.1016/j.yjmcc.2020.05.013] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 05/07/2020] [Accepted: 05/20/2020] [Indexed: 12/29/2022]
Abstract
The mitochondrial permeability transition pore (mPTP) or mitochondrial megachannel is arguably one of the most mysterious phenomena in biology today. mPTP has been at the center of ongoing extensive scientific research for the last several decades. In this review we will discuss recent advances in the field that enhance our understanding of the molecular composition of mPTP, its regulatory mechanisms and its pathophysiological role. We will describe our recent findings on the role of ATP synthase c-subunit ring as a central player in mitochondrial permeability transition and as an important metabolic regulator during development and in degenerative diseases.
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Affiliation(s)
- Nelli Mnatsakanyan
- Section of Endocrinology, Department of Internal Medicine, Yale University, New Haven, CT, USA.
| | - Elizabeth Ann Jonas
- Section of Endocrinology, Department of Internal Medicine, Yale University, New Haven, CT, USA.
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28
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Stancill JS, Happ JT, Broniowska KA, Hogg N, Corbett JA. Peroxiredoxin 1 plays a primary role in protecting pancreatic β-cells from hydrogen peroxide and peroxynitrite. Am J Physiol Regul Integr Comp Physiol 2020; 318:R1004-R1013. [PMID: 32292063 DOI: 10.1152/ajpregu.00011.2020] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Both reactive nitrogen and oxygen species (RNS and ROS), such as nitric oxide, peroxynitrite, and hydrogen peroxide, have been implicated as mediators of pancreatic β-cell damage during the pathogenesis of autoimmune diabetes. While β-cells are thought to be vulnerable to oxidative damage due to reportedly low levels of antioxidant enzymes, such as catalase and glutathione peroxidase, we have shown that they use thioredoxin reductase to detoxify hydrogen peroxide. Thioredoxin reductase is an enzyme that participates in the peroxiredoxin antioxidant cycle. Peroxiredoxins are expressed in β-cells and, when overexpressed, protect against oxidative stress, but the endogenous roles of peroxiredoxins in the protection of β-cells from oxidative damage are unclear. Here, using either glucose oxidase or menadione to continuously deliver hydrogen peroxide, or the combination of dipropylenetriamine NONOate and menadione to continuously deliver peroxynitrite, we tested the hypothesis that β-cells use peroxiredoxins to detoxify both of these reactive species. Either pharmacological peroxiredoxin inhibition with conoidin A or specific depletion of cytoplasmic peroxiredoxin 1 (Prdx1) using siRNAs sensitizes INS 832/13 cells and rat islets to DNA damage and death induced by hydrogen peroxide or peroxynitrite. Interestingly, depletion of peroxiredoxin 2 (Prdx2) had no effect. Together, these results suggest that β-cells use cytoplasmic Prdx1 as a primary defense mechanism against both ROS and RNS.
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Affiliation(s)
- Jennifer S Stancill
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - John T Happ
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin
| | | | - Neil Hogg
- Department of Biophysics, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - John A Corbett
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin
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29
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The relevance of AMP-activated protein kinase in insulin-secreting β cells: a potential target for improving β cell function? J Physiol Biochem 2019; 75:423-432. [PMID: 31691163 PMCID: PMC6920233 DOI: 10.1007/s13105-019-00706-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Accepted: 09/13/2019] [Indexed: 12/12/2022]
Abstract
AMP-activated protein kinase (AMPK) is present in different kinds of metabolically active cells. AMPK is an important intracellular energy sensor and plays a relevant role in whole-body energy homeostasis. AMPK is activated, among others, in response to glucose deprivation, caloric restriction and increased physical activity. Upon activation, AMPK affects metabolic pathways leading to increased formation of ATP and simultaneously reducing ATP-consuming processes. AMPK is also expressed in pancreatic β cells and is largely regulated by glucose, which is the main physiological stimulator of insulin secretion. Results of in vitro studies clearly show that glucose-induced insulin release is associated with a concomitant inhibition of AMPK in β cells. However, pharmacological activation of AMPK significantly potentiates the insulin-secretory response of β cells to glucose and to some other stimuli. This effect is primarily due to increased intracellular calcium concentrations. AMPK is also involved in the regulation of gene expression and may protect β cells against glucolipotoxic conditions. It was shown that in pancreatic islets of humans with type 2 diabetes, AMPK is downregulated. Moreover, studies with animal models demonstrated impaired link between glucose and AMPK activity in pancreatic islet cells. These data suggest that AMPK may be a target for compounds improving the functionality of β cells. However, more studies are required to better elucidate the relevance of AMPK in the (patho)physiology of the insulin-secreting cells.
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30
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Morten KJ, Potter M, Badder L, Sivathondan P, Dragovic R, Neumann A, Gavin J, Shrestha R, Reilly S, Phadwal K, Lodge TA, Borzychowski A, Cookson S, Mitchell C, Morovat A, Simon AK, Uusimaa J, Hynes J, Poulton J. Insights into pancreatic β cell energy metabolism using rodent β cell models. Wellcome Open Res 2019; 2:14. [PMID: 31754635 PMCID: PMC6854877 DOI: 10.12688/wellcomeopenres.10535.3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/16/2019] [Indexed: 01/07/2023] Open
Abstract
Background: Mitochondrial diabetes is primarily caused by β-cell failure, a cell type whose unique properties are important in pathogenesis. Methods: By reducing glucose, we induced energetic stress in two rodent β-cell models to assess effects on cellular function. Results: Culturing rat insulin-secreting INS-1 cells in low glucose conditions caused a rapid reduction in whole cell respiration, associated with elevated mitochondrial reactive oxygen species production, and an altered glucose-stimulated insulin secretion profile. Prolonged exposure to reduced glucose directly impaired mitochondrial function and reduced autophagy. Conclusions: Insulinoma cell lines have a very different bioenergetic profile to many other cell lines and provide a useful model of mechanisms affecting β-cell mitochondrial function.
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Affiliation(s)
- Karl J Morten
- Nuffield Department of Obstetrics & Gynaecology, The Women's Centre, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Michelle Potter
- Nuffield Department of Obstetrics & Gynaecology, The Women's Centre, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Luned Badder
- Nuffield Department of Obstetrics & Gynaecology, The Women's Centre, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Pamela Sivathondan
- Nuffield Department of Obstetrics & Gynaecology, The Women's Centre, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Rebecca Dragovic
- Nuffield Department of Obstetrics & Gynaecology, The Women's Centre, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Abigale Neumann
- Nuffield Department of Obstetrics & Gynaecology, The Women's Centre, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - James Gavin
- Nuffield Department of Obstetrics & Gynaecology, The Women's Centre, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Roshan Shrestha
- Nuffield Department of Obstetrics & Gynaecology, The Women's Centre, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Svetlana Reilly
- Department of Cardiovascular Medicine, John Radcliffe Hospital, Oxford, UK
| | - Kanchan Phadwal
- BRC Translational Immunology Lab, NIHR, Nuffield Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Tiffany A Lodge
- Nuffield Department of Obstetrics & Gynaecology, The Women's Centre, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Angela Borzychowski
- Nuffield Department of Obstetrics & Gynaecology, The Women's Centre, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Sharon Cookson
- Institute of Cellular Medicine, Haematological Sciences, Medical School, Newcastle University, Newcastle upon Tyne, UK
| | - Corey Mitchell
- Nuffield Department of Obstetrics & Gynaecology, The Women's Centre, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | | | | | - Johanna Uusimaa
- Department of Paediatrics, University of Oulu, Oulu, Finland
| | - James Hynes
- Luxcel BioSciences Ltd, BioInnovation Centre, University College Cork, Cork, Ireland
| | - Joanna Poulton
- Nuffield Department of Obstetrics & Gynaecology, The Women's Centre, University of Oxford, John Radcliffe Hospital, Oxford, UK
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31
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Stancill JS, Broniowska KA, Oleson BJ, Naatz A, Corbett JA. Pancreatic β-cells detoxify H 2O 2 through the peroxiredoxin/thioredoxin antioxidant system. J Biol Chem 2019; 294:4843-4853. [PMID: 30659092 DOI: 10.1074/jbc.ra118.006219] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Revised: 01/15/2019] [Indexed: 01/07/2023] Open
Abstract
Oxidative stress is thought to promote pancreatic β-cell dysfunction and contribute to both type 1 and type 2 diabetes. Reactive oxygen species (ROS), such as superoxide and hydrogen peroxide, are mediators of oxidative stress that arise largely from electron leakage during oxidative phosphorylation. Reports that β-cells express low levels of antioxidant enzymes, including catalase and GSH peroxidases, have supported a model in which β-cells are ill-equipped to detoxify ROS. This hypothesis seems at odds with the essential role of β-cells in the control of metabolic homeostasis and organismal survival through exquisite coupling of oxidative phosphorylation, a prominent ROS-producing pathway, to insulin secretion. Using glucose oxidase to deliver H2O2 continuously over time and Amplex Red to measure extracellular H2O2 concentration, we found here that β-cells can remove micromolar levels of this oxidant. This detoxification pathway utilizes the peroxiredoxin/thioredoxin antioxidant system, as selective chemical inhibition or siRNA-mediated depletion of thioredoxin reductase sensitized β-cells to continuously generated H2O2 In contrast, when delivered as a bolus, H2O2 induced the DNA damage response, depleted cellular energy stores, and decreased β-cell viability independently of thioredoxin reductase inhibition. These findings show that β-cells have the capacity to detoxify micromolar levels of H2O2 through a thioredoxin reductase-dependent mechanism and are not as sensitive to oxidative damage as previously thought.
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Affiliation(s)
- Jennifer S Stancill
- From the Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Katarzyna A Broniowska
- From the Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Bryndon J Oleson
- From the Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Aaron Naatz
- From the Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - John A Corbett
- From the Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
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32
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Kraja AT, Liu C, Fetterman JL, Graff M, Have CT, Gu C, Yanek LR, Feitosa MF, Arking DE, Chasman DI, Young K, Ligthart S, Hill WD, Weiss S, Luan J, Giulianini F, Li-Gao R, Hartwig FP, Lin SJ, Wang L, Richardson TG, Yao J, Fernandez EP, Ghanbari M, Wojczynski MK, Lee WJ, Argos M, Armasu SM, Barve RA, Ryan KA, An P, Baranski TJ, Bielinski SJ, Bowden DW, Broeckel U, Christensen K, Chu AY, Corley J, Cox SR, Uitterlinden AG, Rivadeneira F, Cropp CD, Daw EW, van Heemst D, de Las Fuentes L, Gao H, Tzoulaki I, Ahluwalia TS, de Mutsert R, Emery LS, Erzurumluoglu AM, Perry JA, Fu M, Forouhi NG, Gu Z, Hai Y, Harris SE, Hemani G, Hunt SC, Irvin MR, Jonsson AE, Justice AE, Kerrison ND, Larson NB, Lin KH, Love-Gregory LD, Mathias RA, Lee JH, Nauck M, Noordam R, Ong KK, Pankow J, Patki A, Pattie A, Petersmann A, Qi Q, Ribel-Madsen R, Rohde R, Sandow K, Schnurr TM, Sofer T, Starr JM, Taylor AM, Teumer A, Timpson NJ, de Haan HG, Wang Y, Weeke PE, Williams C, Wu H, Yang W, Zeng D, Witte DR, Weir BS, Wareham NJ, Vestergaard H, Turner ST, Torp-Pedersen C, Stergiakouli E, Sheu WHH, Rosendaal FR, Ikram MA, Franco OH, Ridker PM, Perls TT, Pedersen O, Nohr EA, Newman AB, Linneberg A, Langenberg C, Kilpeläinen TO, Kardia SLR, Jørgensen ME, Jørgensen T, Sørensen TIA, Homuth G, Hansen T, Goodarzi MO, Deary IJ, Christensen C, Chen YDI, Chakravarti A, Brandslund I, Bonnelykke K, Taylor KD, Wilson JG, Rodriguez S, Davies G, Horta BL, Thyagarajan B, Rao DC, Grarup N, Davila-Roman VG, Hudson G, Guo X, Arnett DK, Hayward C, Vaidya D, Mook-Kanamori DO, Tiwari HK, Levy D, Loos RJF, Dehghan A, Elliott P, Malik AN, Scott RA, Becker DM, de Andrade M, Province MA, Meigs JB, Rotter JI, North KE. Associations of Mitochondrial and Nuclear Mitochondrial Variants and Genes with Seven Metabolic Traits. Am J Hum Genet 2019; 104:112-138. [PMID: 30595373 PMCID: PMC6323610 DOI: 10.1016/j.ajhg.2018.12.001] [Citation(s) in RCA: 76] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Accepted: 12/06/2018] [Indexed: 12/16/2022] Open
Abstract
Mitochondria (MT), the major site of cellular energy production, are under dual genetic control by 37 mitochondrial DNA (mtDNA) genes and numerous nuclear genes (MT-nDNA). In the CHARGEmtDNA+ Consortium, we studied genetic associations of mtDNA and MT-nDNA associations with body mass index (BMI), waist-hip-ratio (WHR), glucose, insulin, HOMA-B, HOMA-IR, and HbA1c. This 45-cohort collaboration comprised 70,775 (insulin) to 170,202 (BMI) pan-ancestry individuals. Validation and imputation of mtDNA variants was followed by single-variant and gene-based association testing. We report two significant common variants, one in MT-ATP6 associated (p ≤ 5E-04) with WHR and one in the D-loop with glucose. Five rare variants in MT-ATP6, MT-ND5, and MT-ND6 associated with BMI, WHR, or insulin. Gene-based meta-analysis identified MT-ND3 associated with BMI (p ≤ 1E-03). We considered 2,282 MT-nDNA candidate gene associations compiled from online summary results for our traits (20 unique studies with 31 dataset consortia's genome-wide associations [GWASs]). Of these, 109 genes associated (p ≤ 1E-06) with at least 1 of our 7 traits. We assessed regulatory features of variants in the 109 genes, cis- and trans-gene expression regulation, and performed enrichment and protein-protein interactions analyses. Of the identified mtDNA and MT-nDNA genes, 79 associated with adipose measures, 49 with glucose/insulin, 13 with risk for type 2 diabetes, and 18 with cardiovascular disease, indicating for pleiotropic effects with health implications. Additionally, 21 genes related to cholesterol, suggesting additional important roles for the genes identified. Our results suggest that mtDNA and MT-nDNA genes and variants reported make important contributions to glucose and insulin metabolism, adipocyte regulation, diabetes, and cardiovascular disease.
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Affiliation(s)
- Aldi T Kraja
- Division of Statistical Genomics, Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St Louis, MO 63110, USA.
| | - Chunyu Liu
- Department of Biostatistics, Boston University School of Public Health, Boston, MA 02118, USA
| | - Jessica L Fetterman
- Evans Department of Medicine and Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA 02118, USA
| | - Mariaelisa Graff
- Department of Epidemiology, University of North Carolina, Chapel Hill, NC 27516, USA
| | - Christian Theil Have
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200, Denmark
| | - Charles Gu
- Division of Biostatistics, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Lisa R Yanek
- GeneSTAR Research Program, Division of General Internal Medicine, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Mary F Feitosa
- Division of Statistical Genomics, Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Dan E Arking
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Daniel I Chasman
- Division of Preventive Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Kristin Young
- Department of Epidemiology, University of North Carolina, Chapel Hill, NC 27516, USA
| | - Symen Ligthart
- Department of Epidemiology, Erasmus University Medical Center, Rotterdam 3015 CE, the Netherlands
| | - W David Hill
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Department of Psychology, University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Stefan Weiss
- Interfaculty Institute for Genetics and Functional Genomics, University Medicine and University of Greifswald, Greifswald 17475, Germany
| | - Jian'an Luan
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Franco Giulianini
- Division of Preventive Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Ruifang Li-Gao
- Department of Clinical Epidemiology, Leiden University Medical Center, Leiden 2333 ZA, the Netherlands
| | - Fernando P Hartwig
- Postgraduate Program in Epidemiology, Federal University of Pelotas, Pelotas 96020-220, Brazil; MRC Integrative Epidemiology Unit (IEU), Population Health Sciences, University of Bristol, Bristol BS8 2BN, UK
| | - Shiow J Lin
- Division of Statistical Genomics, Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Lihua Wang
- Division of Statistical Genomics, Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Tom G Richardson
- MRC Integrative Epidemiology Unit (IEU), Population Health Sciences, University of Bristol, Bristol BS8 2BN, UK
| | - Jie Yao
- Institute for Translational Genomics and Population Sciences, LABioMed and Department of Pediatrics, at Harbor-UCLA Medical Center, Torrance, CA 90502, USA
| | - Eliana P Fernandez
- Department of Epidemiology, Erasmus University Medical Center, Rotterdam 3015 CE, the Netherlands
| | - Mohsen Ghanbari
- Department of Epidemiology, Erasmus University Medical Center, Rotterdam 3015 CE, the Netherlands
| | - Mary K Wojczynski
- Division of Statistical Genomics, Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Wen-Jane Lee
- Department of Medical Research, Taichung Veterans General Hospital, Taichung 407, Taiwan; Department of Social Work, Tunghai University, Taichung 407, Taiwan
| | - Maria Argos
- Department of Epidemiology and Biostatistics, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Sebastian M Armasu
- Division of Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic, Rochester, MN 55905, USA
| | - Ruteja A Barve
- Department of Genetics, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Kathleen A Ryan
- School of Medicine, Division of Endocrinology, Diabetes and Nutrition, and Program for Personalized and Genomic Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Ping An
- Division of Statistical Genomics, Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Thomas J Baranski
- Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Suzette J Bielinski
- Department of Health Sciences Research, Mayo Clinic, Rochester, MN 55905, USA
| | - Donald W Bowden
- Center for Diabetes Research, Wake Forest School of Medicine, Cincinnati, OH 45206, USA
| | - Ulrich Broeckel
- Human and Molecular Genetics Center, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Kaare Christensen
- The Danish Aging Research Center, University of Southern Denmark, Odense 5000, Denmark
| | - Audrey Y Chu
- Division of Preventive Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Janie Corley
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Department of Psychology, University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Simon R Cox
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Department of Psychology, University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Andre G Uitterlinden
- Department of Internal Medicine, Erasmus Medical Center, 3000 CA Rotterdam, the Netherlands
| | - Fernando Rivadeneira
- Department of Internal Medicine, Erasmus Medical Center, 3000 CA Rotterdam, the Netherlands
| | - Cheryl D Cropp
- Samford University McWhorter School of Pharmacy, Birmingham, Alabama, Translational Genomics Research Institute (TGen), Phoenix, AZ 35229, USA
| | - E Warwick Daw
- Division of Statistical Genomics, Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Diana van Heemst
- Department of Internal Medicine, Section of Gerontology and Geriatrics, Leiden University Medical Center, Leiden 2333 ZA, the Netherlands
| | - Lisa de Las Fuentes
- Cardiovascular Division, Department of Medicine, Washington University School of Medicine, St Louis, MO 63110, USA
| | - He Gao
- Department of Biostatistics and Epidemiology, MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London W2 1PG, UK
| | - Ioanna Tzoulaki
- Department of Biostatistics and Epidemiology, MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London W2 1PG, UK; Department of Hygiene and Epidemiology, University of Ioannina, Ioannina 45110, Greece
| | | | - Renée de Mutsert
- Department of Clinical Epidemiology, Leiden University Medical Center, Leiden 2333 ZA, the Netherlands
| | - Leslie S Emery
- Department of Biostatistics, University of Washington, Seattle, WA 98195, USA
| | | | - James A Perry
- School of Medicine, Division of Endocrinology, Diabetes and Nutrition, and Program for Personalized and Genomic Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Mao Fu
- School of Medicine, Division of Endocrinology, Diabetes and Nutrition, and Program for Personalized and Genomic Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Nita G Forouhi
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Zhenglong Gu
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
| | - Yang Hai
- Institute for Translational Genomics and Population Sciences, LABioMed and Department of Pediatrics, at Harbor-UCLA Medical Center, Torrance, CA 90502, USA
| | - Sarah E Harris
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Centre for Genomic and Experimental Medicine, Medical Genetics Section, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Gibran Hemani
- MRC Integrative Epidemiology Unit (IEU), Population Health Sciences, University of Bristol, Bristol BS8 2BN, UK
| | - Steven C Hunt
- Department of Internal Medicine, University of Utah, Salt Lake City, UT 84132, USA; Department of Genetic Medicine, Weill Cornell Medicine, PO Box 24144, Doha, Qatar
| | - Marguerite R Irvin
- Department of Epidemiology, School of Public Health, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Anna E Jonsson
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200, Denmark
| | - Anne E Justice
- Department of Epidemiology, University of North Carolina, Chapel Hill, NC 27516, USA; Biomedical and Translational Informatics, Geisinger Health, Danville, PA 17822, USA
| | - Nicola D Kerrison
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Nicholas B Larson
- Department of Health Sciences Research, Mayo Clinic, Rochester, MN 55905, USA
| | - Keng-Hung Lin
- Department of Ophthalmology, Taichung Veterans General Hospital, Taichung 407, Taiwan
| | - Latisha D Love-Gregory
- Genomics & Pathology Services, Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Rasika A Mathias
- GeneSTAR Research Program, Division of General Internal Medicine, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; GeneSTAR Research Program, Divisions of Allergy and Clinical Immunology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Joseph H Lee
- Taub Institute for Research on Alzheimer disease and the Aging Brain, Columbia University Medical Center, New York, NY 10032, USA
| | - Matthias Nauck
- Institute of Clinical Chemistry and Laboratory Medicine, University Medicine Greifswald, Greifswald 17475, Germany
| | - Raymond Noordam
- Department of Internal Medicine, Section of Gerontology and Geriatrics, Leiden University Medical Center, Leiden 2333 ZA, the Netherlands
| | - Ken K Ong
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - James Pankow
- University of Minnesota School of Public Health, Division of Epidemiology and Community Health, Minneapolis, MN 55454, USA
| | - Amit Patki
- Department of Biostatistics, School of Public Health, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Alison Pattie
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Department of Psychology, University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Astrid Petersmann
- Institute of Clinical Chemistry and Laboratory Medicine, University Medicine Greifswald, Greifswald 17475, Germany
| | - Qibin Qi
- Department of Epidemiology & Population Health, Albert Einstein School of Medicine, Bronx, NY 10461, USA
| | - Rasmus Ribel-Madsen
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200, Denmark; Department of Endocrinology, Diabetes and Metabolism, Rigshospitalet, Copenhagen University Hospital, 2100 Copenhagen, Denmark; The Danish Diabetes Academy, 5000 Odense, Denmark
| | - Rebecca Rohde
- Department of Epidemiology, University of North Carolina, Chapel Hill, NC 27516, USA
| | - Kevin Sandow
- Institute for Translational Genomics and Population Sciences, LABioMed and Department of Pediatrics, at Harbor-UCLA Medical Center, Torrance, CA 90502, USA
| | - Theresia M Schnurr
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200, Denmark
| | - Tamar Sofer
- Department of Biostatistics, University of Washington, Seattle, WA 98195, USA; Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - John M Starr
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Department of Psychology, University of Edinburgh, Edinburgh EH8 9JZ, UK; Alzheimer Scotland Dementia Research Centre, University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Adele M Taylor
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Department of Psychology, University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Alexander Teumer
- Institute for Community Medicine, University Medicine Greifswald, 17475 Greifswald, Germany
| | - Nicholas J Timpson
- MRC Integrative Epidemiology Unit (IEU), Population Health Sciences, University of Bristol, Bristol BS8 2BN, UK
| | - Hugoline G de Haan
- Department of Clinical Epidemiology, Leiden University Medical Center, Leiden 2333 ZA, the Netherlands
| | - Yujie Wang
- Department of Epidemiology, University of North Carolina, Chapel Hill, NC 27516, USA
| | - Peter E Weeke
- Department of Cardiology, The Heart Centre, Rigshospitalet, University of Copenhagen, Copenhagen 2100, Denmark
| | - Christine Williams
- Division of Statistical Genomics, Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Hongsheng Wu
- Computer Science and Networking, Wentworth Institute of Technology, Boston, MA 02115, USA
| | - Wei Yang
- Genome Technology Access Center, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Donglin Zeng
- Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Daniel R Witte
- Department of Public Health, Section of Epidemiology, Aarhus University, Denmark, Danish Diabetes Academy, Odense University Hospital, 5000 Odense, Denmark
| | - Bruce S Weir
- Department of Biostatistics, University of Washington, Seattle, WA 98195, USA
| | - Nicholas J Wareham
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Henrik Vestergaard
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200, Denmark; Steno Diabetes Center Copenhagen, Copenhagen 2820, Denmark
| | - Stephen T Turner
- Division of Nephrology and Hypertension, Department of Cardiovascular Diseases, Mayo Clinic, Rochester, MN 55902, USA
| | - Christian Torp-Pedersen
- Department of Health Science and Technology, Aalborg University Hospital, Aalborg 9220, Denmark
| | - Evie Stergiakouli
- MRC Integrative Epidemiology Unit (IEU), Population Health Sciences, University of Bristol, Bristol BS8 2BN, UK
| | - Wayne Huey-Herng Sheu
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Taichung Veterans General Hospital, Taichung 407, Taiwan; Institute of Medical Technology, National Chung-Hsing University, Taichung 402, Taiwan; School of Medicine, National Defense Medical Center, Taipei 114, Taiwan; School of Medicine, National Yang-Ming University, Taipei 112, Taiwan
| | - Frits R Rosendaal
- Department of Clinical Epidemiology, Leiden University Medical Center, Leiden 2333 ZA, the Netherlands
| | - M Arfan Ikram
- Department of Epidemiology, Erasmus University Medical Center, Rotterdam 3015 CE, the Netherlands
| | - Oscar H Franco
- Department of Epidemiology, Erasmus University Medical Center, Rotterdam 3015 CE, the Netherlands; Institute of Social and Preventive Medicine (ISPM), University of Bern, 3012 Bern, Switzerland
| | - Paul M Ridker
- Division of Preventive Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Thomas T Perls
- Department of Medicine, Geriatrics Section, Boston University School of Medicine and Boston Medical Center, Boston, MA 02118, USA
| | - Oluf Pedersen
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200, Denmark
| | - Ellen A Nohr
- Research Unit for Gynecology and Obstetrics, Department of Clinical Research, University of Southern Denmark, 5000 Odense, Denmark
| | - Anne B Newman
- Department of Epidemiology, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Allan Linneberg
- Department of Clinical Experimental Research, Rigshospitalet, Copenhagen 2200, Denmark; Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200, Denmark; The Center for Clinical Research and Prevention, Bispebjerg and Frederiksberg Hospital, The Capital Region, Copenhagen 2000, Denmark
| | - Claudia Langenberg
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Tuomas O Kilpeläinen
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200, Denmark
| | - Sharon L R Kardia
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI 48109, USA
| | | | - Torben Jørgensen
- Research Centre for Prevention and Health, Glostrup Hospital, Glostrup 2600, Denmark; Department of Public Health, Faculty of Health Sciences, University of Copenhagen, Copenhagen 1014, Denmark; Faculty of Medicine, Aalborg University, Aalborg 9100, Denmark
| | - Thorkild I A Sørensen
- Novo Nordisk Foundation Center for Basic Metabolic Research (Section of Metabolic Genetics) and Department of Public Health (Section on Epidemiology), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200N, Denmark
| | - Georg Homuth
- Interfaculty Institute for Genetics and Functional Genomics, University Medicine and University of Greifswald, Greifswald 17475, Germany
| | - Torben Hansen
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200, Denmark
| | - Mark O Goodarzi
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Ian J Deary
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Department of Psychology, University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Cramer Christensen
- Department of Internal Medicine, Section of Endocrinology, Vejle Lillebaelt Hospital, 7100 Vejle, Denmark
| | - Yii-Der Ida Chen
- Institute for Translational Genomics and Population Sciences, LABioMed and Department of Pediatrics, at Harbor-UCLA Medical Center, Torrance, CA 90502, USA
| | - Aravinda Chakravarti
- Center for Complex Disease Genomics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Ivan Brandslund
- Department of Clinical Biochemistry, Vejle Hospital, 7100 Vejle, Denmark; Institute of Regional Health Research, University of Southern Denmark, 5000 Odense C, Denmark
| | - Klaus Bonnelykke
- Copenhagen Prospective Studies on Asthma in Childhood, Copenhagen University Hospital, Gentofte & Naestved 2820, Denmark; Health Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Kent D Taylor
- Institute for Translational Genomics and Population Sciences, LABioMed and Department of Pediatrics, at Harbor-UCLA Medical Center, Torrance, CA 90502, USA
| | - James G Wilson
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, MS 39216, USA
| | - Santiago Rodriguez
- MRC Integrative Epidemiology Unit (IEU), Population Health Sciences, University of Bristol, Bristol BS8 2BN, UK
| | - Gail Davies
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Department of Psychology, University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Bernardo L Horta
- Postgraduate Program in Epidemiology, Federal University of Pelotas, Pelotas 96020-220, Brazil
| | - Bharat Thyagarajan
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN 55455, USA
| | - D C Rao
- Division of Biostatistics, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Niels Grarup
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200, Denmark
| | - Victor G Davila-Roman
- Cardiovascular Division, Department of Medicine, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Gavin Hudson
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK
| | - Xiuqing Guo
- Institute for Translational Genomics and Population Sciences, LABioMed and Department of Pediatrics, at Harbor-UCLA Medical Center, Torrance, CA 90502, USA
| | - Donna K Arnett
- University of Kentucky, College of Public Health, Lexington, KY 40508, USA
| | - Caroline Hayward
- MRC Human Genetics Unit, University of Edinburgh, Institute of Genetics and Molecular Medicine, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Dhananjay Vaidya
- GeneSTAR Research Program, Division of General Internal Medicine, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Dennis O Mook-Kanamori
- Department of Clinical Epidemiology, Leiden University Medical Center, Leiden 2333 ZA, the Netherlands; Department of Public Health and Primary Care, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands
| | - Hemant K Tiwari
- Department of Biostatistics, School of Public Health, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Daniel Levy
- The Framingham Heart Study, Framingham, MA, USA; The Population Sciences Branch, NHLBI/NIH, Bethesda, MD 20892, USA
| | - Ruth J F Loos
- Charles Bronfman Institute for Personalized Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Genetics of Obesity and Related Traits Program, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Abbas Dehghan
- Department of Biostatistics and Epidemiology, MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London W2 1PG, UK
| | - Paul Elliott
- Department of Biostatistics and Epidemiology, MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London W2 1PG, UK
| | - Afshan N Malik
- King's College London, Department of Diabetes, School of Life Course, Faculty of Life Sciences and Medicine, London SE1 1NN, UK
| | - Robert A Scott
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Diane M Becker
- GeneSTAR Research Program, Division of General Internal Medicine, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Mariza de Andrade
- Division of Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic, Rochester, MN 55905, USA
| | - Michael A Province
- Division of Statistical Genomics, Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - James B Meigs
- Department of Medicine, Harvard Medical School, Boston, MA 02115, USA; Division of General Internal Medicine, Massachusetts General Hospital, Boston 02114, MA, USA; Program in Medical and Population Genetics, Broad Institute, Boston, MA 02142, USA
| | - Jerome I Rotter
- Institute for Translational Genomics and Population Sciences, LABioMed and Department of Pediatrics, at Harbor-UCLA Medical Center, Torrance, CA 90502, USA
| | - Kari E North
- Department of Epidemiology, University of North Carolina, Chapel Hill, NC 27516, USA.
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Adam J, Ramracheya R, Chibalina MV, Ternette N, Hamilton A, Tarasov AI, Zhang Q, Rebelato E, Rorsman NJG, Martín-Del-Río R, Lewis A, Özkan G, Do HW, Spégel P, Saitoh K, Kato K, Igarashi K, Kessler BM, Pugh CW, Tamarit-Rodriguez J, Mulder H, Clark A, Frizzell N, Soga T, Ashcroft FM, Silver A, Pollard PJ, Rorsman P. Fumarate Hydratase Deletion in Pancreatic β Cells Leads to Progressive Diabetes. Cell Rep 2018; 20:3135-3148. [PMID: 28954230 PMCID: PMC5637167 DOI: 10.1016/j.celrep.2017.08.093] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 07/27/2017] [Accepted: 08/29/2017] [Indexed: 12/31/2022] Open
Abstract
We explored the role of the Krebs cycle enzyme fumarate hydratase (FH) in glucose-stimulated insulin secretion (GSIS). Mice lacking Fh1 in pancreatic β cells (Fh1βKO mice) appear normal for 6–8 weeks but then develop progressive glucose intolerance and diabetes. Glucose tolerance is rescued by expression of mitochondrial or cytosolic FH but not by deletion of Hif1α or Nrf2. Progressive hyperglycemia in Fh1βKO mice led to dysregulated metabolism in β cells, a decrease in glucose-induced ATP production, electrical activity, cytoplasmic [Ca2+]i elevation, and GSIS. Fh1 loss resulted in elevated intracellular fumarate, promoting succination of critical cysteines in GAPDH, GMPR, and PARK 7/DJ-1 and cytoplasmic acidification. Intracellular fumarate levels were increased in islets exposed to high glucose and in islets from human donors with type 2 diabetes (T2D). The impaired GSIS in islets from diabetic Fh1βKO mice was ameliorated after culture under normoglycemic conditions. These studies highlight the role of FH and dysregulated mitochondrial metabolism in T2D. Fh1 loss in β cells causes progressive Hif1α-independent diabetes Fh1 loss in β cells impairs ATP generation, electrical activity, and GSIS Elevated fumarate is a feature of diabetic murine and human islets “Normoglycemia” restores GSIS in Fh1βKO islets
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Affiliation(s)
- Julie Adam
- Radcliffe Department of Medicine, OCDEM, Churchill Hospital, University of Oxford, Oxford OX3 7LE, UK; Nuffield Department of Medicine, Henry Wellcome Building for Molecular Physiology, University of Oxford, Oxford OX3 7BN, UK; Nuffield Department of Medicine, NDMRB, University of Oxford, Oxford OX3 7FZ, UK.
| | - Reshma Ramracheya
- Radcliffe Department of Medicine, OCDEM, Churchill Hospital, University of Oxford, Oxford OX3 7LE, UK
| | - Margarita V Chibalina
- Radcliffe Department of Medicine, OCDEM, Churchill Hospital, University of Oxford, Oxford OX3 7LE, UK
| | - Nicola Ternette
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7FZ, UK
| | - Alexander Hamilton
- Radcliffe Department of Medicine, OCDEM, Churchill Hospital, University of Oxford, Oxford OX3 7LE, UK
| | - Andrei I Tarasov
- Radcliffe Department of Medicine, OCDEM, Churchill Hospital, University of Oxford, Oxford OX3 7LE, UK
| | - Quan Zhang
- Radcliffe Department of Medicine, OCDEM, Churchill Hospital, University of Oxford, Oxford OX3 7LE, UK
| | - Eduardo Rebelato
- Radcliffe Department of Medicine, OCDEM, Churchill Hospital, University of Oxford, Oxford OX3 7LE, UK; Department of Biophysics, Federal University of Sao Paulo, Sao Paulo 04023-062, Brazil
| | - Nils J G Rorsman
- Radcliffe Department of Medicine, OCDEM, Churchill Hospital, University of Oxford, Oxford OX3 7LE, UK
| | - Rafael Martín-Del-Río
- Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Ramón y Cajal Hospital, Madrid, Spain
| | - Amy Lewis
- Centre for Genomics and Child Health, Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London E1 2AT, UK
| | - Gizem Özkan
- Nuffield Department of Medicine, Henry Wellcome Building for Molecular Physiology, University of Oxford, Oxford OX3 7BN, UK
| | - Hyun Woong Do
- Radcliffe Department of Medicine, OCDEM, Churchill Hospital, University of Oxford, Oxford OX3 7LE, UK
| | - Peter Spégel
- Centre for Analysis and Synthesis, Department of Chemistry, Lund University, Box 124, 221 00 Lund, Sweden
| | - Kaori Saitoh
- Institute for Advanced Biosciences, Keio University, 246-2 Mizukami, Tsuruoka, Yamagata 997-0052, Japan
| | - Keiko Kato
- Institute for Advanced Biosciences, Keio University, 246-2 Mizukami, Tsuruoka, Yamagata 997-0052, Japan
| | - Kaori Igarashi
- Institute for Advanced Biosciences, Keio University, 246-2 Mizukami, Tsuruoka, Yamagata 997-0052, Japan
| | - Benedikt M Kessler
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7FZ, UK
| | - Christopher W Pugh
- Nuffield Department of Medicine, Henry Wellcome Building for Molecular Physiology, University of Oxford, Oxford OX3 7BN, UK; Nuffield Department of Medicine, NDMRB, University of Oxford, Oxford OX3 7FZ, UK
| | - Jorge Tamarit-Rodriguez
- Biochemistry Department, School of Medicine, Complutense University of Madrid, 28040 Madrid, Spain
| | - Hindrik Mulder
- Lund University Diabetes Centre, Unit of Molecular Metabolism, Clinical Research Centre, Malmo University Hospital, 20502 Malmo, Sweden
| | - Anne Clark
- Radcliffe Department of Medicine, OCDEM, Churchill Hospital, University of Oxford, Oxford OX3 7LE, UK
| | - Norma Frizzell
- Department of Pharmacology, Physiology & Neuroscience, School of Medicine, University of South Carolina, Columbia, SC 29208, USA
| | - Tomoyoshi Soga
- Institute for Advanced Biosciences, Keio University, 246-2 Mizukami, Tsuruoka, Yamagata 997-0052, Japan
| | - Frances M Ashcroft
- Department of Physiology, Anatomy and Genetics, University of Oxford, Parks Road, Oxford OX1 3PT, UK
| | - Andrew Silver
- Centre for Genomics and Child Health, Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London E1 2AT, UK
| | - Patrick J Pollard
- Nuffield Department of Medicine, Henry Wellcome Building for Molecular Physiology, University of Oxford, Oxford OX3 7BN, UK; Department of Physiology, Institute of Neuroscience and Physiology, University of Göteborg, 405 30 Göteborg, Sweden
| | - Patrik Rorsman
- Radcliffe Department of Medicine, OCDEM, Churchill Hospital, University of Oxford, Oxford OX3 7LE, UK; Department of Physiology, Institute of Neuroscience and Physiology, University of Göteborg, 405 30 Göteborg, Sweden.
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Wilson DF, Cember ATJ, Matschinsky FM. The thermodynamic basis of glucose-stimulated insulin release: a model of the core mechanism. Physiol Rep 2018; 5:5/12/e13327. [PMID: 28655753 PMCID: PMC5492210 DOI: 10.14814/phy2.13327] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2017] [Revised: 05/23/2017] [Accepted: 05/24/2017] [Indexed: 11/24/2022] Open
Abstract
A model for glucose sensing by pancreatic β-cells is developed and compared with the available experimental data. The model brings together mathematical representations for the activities of the glucose sensor, glucokinase, and oxidative phosphorylation. Glucokinase produces glucose 6-phosphate (G-6-P) in an irreversible reaction that determines glycolytic flux. The primary products of glycolysis are NADH and pyruvate. The NADH is reoxidized and the reducing equivalents transferred to oxidative phosphorylation by the glycerol phosphate shuttle, and some of the pyruvate is oxidized by pyruvate dehydrogenase and enters the citric acid cycle. These reactions are irreversible and result in a glucose concentration-dependent reduction of the intramitochondrial NAD pool. This increases the electrochemical energy coupled to ATP synthesis and thereby the cellular energy state ([ATP]/[ADP][Pi]). ATP and Pi are 10-100 times greater than ADP, so the increase in energy state is primarily through decrease in ADP The decrease in ADP is considered responsible for altering ion channel conductance and releasing insulin. Applied to the reported glucose concentration-dependent release of insulin by perifused islet preparations (Doliba et al. 2012), the model predicts that the dependence of insulin release on ADP is strongly cooperative with a threshold of about 30 μmol/L and a negative Hill coefficient near -5.5. The predicted cellular energy state, ADP, creatine phosphate/creatine ratio, and cytochrome c reduction, including their dependence on glucose concentration, are consistent with experimental data. The ability of the model to predict behavior consistent with experiment is an invaluable resource for understanding glucose sensing and planning experiments.
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Affiliation(s)
- David F Wilson
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Abigail T J Cember
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Franz M Matschinsky
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
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35
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Lao-On U, Attwood PV, Jitrapakdee S. Roles of pyruvate carboxylase in human diseases: from diabetes to cancers and infection. J Mol Med (Berl) 2018; 96:237-247. [PMID: 29362846 DOI: 10.1007/s00109-018-1622-0] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Revised: 01/09/2018] [Accepted: 01/15/2018] [Indexed: 02/08/2023]
Abstract
Pyruvate carboxylase (PC), an anaplerotic enzyme, plays an essential role in various cellular metabolic pathways including gluconeogenesis, de novo fatty acid synthesis, amino acid synthesis, and glucose-induced insulin secretion. Deregulation of PC expression or activity has long been known to be associated with metabolic syndrome in several rodent models. Accumulating data in the past decade clearly showed that deregulation of PC expression is associated with type 2 diabetes in humans, while targeted inhibition of PC expression in a mouse model reduced adiposity and improved insulin sensitivity in diet-induced type 2 diabetes. More recent studies also show that PC is strongly involved in tumorigenesis in several cancers, including breast, non-small cell lung cancer, glioblastoma, renal carcinoma, and gall bladder. Systems metabolomics analysis of these cancers identified pyruvate carboxylation as an essential metabolic hub that feeds carbon skeletons of downstream metabolites of oxaloacetate into the biosynthesis of various cellular components including membrane lipids, nucleotides, amino acids, and the redox control. Inhibition or down-regulation of PC expression in several cancers markedly impairs their growth ex vivo and in vivo, drawing attention to PC as an anti-cancer target. PC has also exhibited a moonlight function by interacting with immune surveillance that can either promote or block viral infection. In certain pathogenic bacteria, PC is essential for infection, replication, and maintenance of their virulence phenotype.
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Affiliation(s)
- Udom Lao-On
- Gene Expression and Metabolic Science Research Laboratory, Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand
| | - Paul V Attwood
- School of Molecular Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, WA, 6009, Australia
| | - Sarawut Jitrapakdee
- Gene Expression and Metabolic Science Research Laboratory, Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand.
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36
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Morten KJ, Potter M, Badder L, Sivathondan P, Dragovic R, Neumann A, Gavin J, Shrestha R, Reilly S, Phadwal K, Lodge TA, Borzychowski A, Cookson S, Mitchell C, Morovat A, Simon AK, Uusimaa J, Hynes J, Poulton J. Insights into pancreatic β cell energy metabolism using rodent β cell models. Wellcome Open Res 2017; 2:14. [DOI: 10.12688/wellcomeopenres.10535.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/14/2019] [Indexed: 11/20/2022] Open
Abstract
Background: Mitochondrial diabetes is primarily caused by β-cell failure, a cell type whose unique properties are important in pathogenesis. Methods: By reducing glucose, we induced energetic stress in two rodent β-cell models to assess effects on cellular function. Results: Culturing rat insulin-secreting INS-1 cells in low glucose conditions caused a rapid reduction in whole cell respiration, associated with elevated mitochondrial reactive oxygen species production, and an altered glucose-stimulated insulin secretion profile. Prolonged exposure to reduced glucose directly impaired mitochondrial function and reduced autophagy. Conclusions: Insulinoma cell lines have a very different bioenergetic profile to many other cell lines and provide a useful model of mechanisms affecting β-cell mitochondrial function.
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37
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Lamontagne J, Al-Mass A, Nolan CJ, Corkey BE, Madiraju SRM, Joly E, Prentki M. Identification of the signals for glucose-induced insulin secretion in INS1 (832/13) β-cells using metformin-induced metabolic deceleration as a model. J Biol Chem 2017; 292:19458-19468. [PMID: 28972173 DOI: 10.1074/jbc.m117.808105] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 09/13/2017] [Indexed: 12/23/2022] Open
Abstract
Metabolic deceleration in pancreatic β-cells is associated with inhibition of glucose-induced insulin secretion (GIIS), but only in the presence of intermediate/submaximal glucose concentrations. Here, we used acute metformin treatment as a tool to induce metabolic deceleration in INS1 (832/13) β-cells, with the goal of identifying key pathways and metabolites involved in GIIS. Metabolites and pathways previously implicated as signals for GIIS were measured in the cells at 2-25 mm glucose, with or without 5 mm metformin. We defined three criteria to identify candidate signals: 1) glucose-responsiveness, 2) sensitivity to metformin-induced inhibition of the glucose effect at intermediate glucose concentrations, and 3) alleviation of metformin inhibition by elevated glucose concentrations. Despite the lack of recovery from metformin-induced impairment of mitochondrial energy metabolism (glucose oxidation, O2 consumption, and ATP production), insulin secretion was almost completely restored at elevated glucose concentrations. Meeting the criteria for candidates involved in promoting GIIS were the following metabolic indicators and metabolites: cytosolic NAD+/NADH ratio (inferred from the dihydroxyacetone phosphate:glycerol-3-phosphate ratio), mitochondrial membrane potential, ADP, Ca2+, 1-monoacylglycerol, diacylglycerol, malonyl-CoA, and HMG-CoA. On the contrary, most of the purine and nicotinamide nucleotides, acetoacetyl-CoA, H2O2, reduced glutathione, and 2-monoacylglycerol were not glucose-responsive. Overall these results underscore the significance of mitochondrial energy metabolism-independent signals in GIIS regulation; in particular, the candidate lipid signaling molecules 1-monoacylglycerol, diacylglycerol, and malonyl-CoA; the predominance of KATP/Ca2+ signaling control by low ADP·Mg2+ rather than by high ATP levels; and a role for a more oxidized state (NAD+/NADH) in the cytosol during GIIS that favors high glycolysis rates.
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Affiliation(s)
- Julien Lamontagne
- From the Molecular Nutrition Unit and Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec H2X 0A9, Canada
| | - Anfal Al-Mass
- From the Molecular Nutrition Unit and Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec H2X 0A9, Canada.,the Department of Medicine, McGill University, Montréal, Québec H4A 3J1, Canada
| | - Christopher J Nolan
- the Department of Endocrinology, Canberra Hospital and the Medical School, Australian National University, Canberra ACT 2605, Australia, and
| | - Barbara E Corkey
- the Department of Medicine, Obesity Research Center, Boston University School of Medicine, Boston, Massachusetts 02118
| | - S R Murthy Madiraju
- From the Molecular Nutrition Unit and Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec H2X 0A9, Canada
| | - Erik Joly
- From the Molecular Nutrition Unit and Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec H2X 0A9, Canada
| | - Marc Prentki
- From the Molecular Nutrition Unit and Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec H2X 0A9, Canada, .,the Departments of Nutrition and Biochemistry, Université de Montréal, Montréal, Québec H3T 1J4, Canada
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38
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Jensen MV, Gooding J, Ferdaoussi M, Dai XQ, MacDonald PE, Newgard CB. Metabolomics applied to islet nutrient sensing mechanisms. Diabetes Obes Metab 2017; 19 Suppl 1:90-94. [PMID: 28880482 PMCID: PMC5929146 DOI: 10.1111/dom.13010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 05/09/2017] [Accepted: 05/12/2017] [Indexed: 12/16/2022]
Abstract
After multiple decades of investigation, the precise mechanisms involved in fuel-stimulated insulin secretion are still being revealed. One avenue for gaining deeper knowledge is to apply emergent tools of "metabolomics," involving mass spectrometry and nuclear magnetic resonance-based profiling of islet cells in their fuel-stimulated compared with basal states. The current article summarizes recent insights gained from application of metabolomics tools to the specific process of glucose-stimulated insulin secretion, revealing 2 new mechanisms that may provide targets for improving insulin secretion in diabetes.
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Affiliation(s)
- Mette V. Jensen
- Sarah W. Stedman Nutrition and Metabolism Center, Duke Molecular Physiology Institute, Duke University Medical Center, Durham, NC 27701
| | - Jessica Gooding
- Sarah W. Stedman Nutrition and Metabolism Center, Duke Molecular Physiology Institute, Duke University Medical Center, Durham, NC 27701
| | - Mourad Ferdaoussi
- Department of Pharmacology and Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada, T6G2R3
| | - Xiao-Qing Dai
- Department of Pharmacology and Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada, T6G2R3
| | - Patrick E. MacDonald
- Department of Pharmacology and Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada, T6G2R3
| | - Christopher B. Newgard
- Sarah W. Stedman Nutrition and Metabolism Center, Duke Molecular Physiology Institute, Duke University Medical Center, Durham, NC 27701
- Corresponding Author: Christopher B. Newgard, PhD, Duke Molecular Physiology Institute, 300 North Duke Street, Durham, NC 27701, , Phone: (919) 668-6059
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39
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Abstract
Pancreatic islet β cells secrete insulin in response to nutrient secretagogues, like glucose, dependent on calcium influx and nutrient metabolism. One of the most intriguing qualities of β cells is their ability to use metabolism to amplify the amount of secreted insulin independent of further alterations in intracellular calcium. Many years studying this amplifying process have shaped our current understanding of β cell stimulus-secretion coupling; yet, the exact mechanisms of amplification have been elusive. Recent studies utilizing metabolomics, computational modeling, and animal models have progressed our understanding of the metabolic amplifying pathway of insulin secretion from the β cell. New approaches will be discussed which offer in-roads to a more complete model of β cell function. The development of β cell therapeutics may be aided by such a model, facilitating the targeting of aspects of the metabolic amplifying pathway which are unique to the β cell.
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Affiliation(s)
- Michael A Kalwat
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX, United States.
| | - Melanie H Cobb
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX, United States
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40
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Taylor EB. Functional Properties of the Mitochondrial Carrier System. Trends Cell Biol 2017; 27:633-644. [PMID: 28522206 DOI: 10.1016/j.tcb.2017.04.004] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 04/16/2017] [Accepted: 04/18/2017] [Indexed: 11/28/2022]
Abstract
The mitochondrial carrier system (MCS) transports small molecules between mitochondria and the cytoplasm. It is integral to the core mitochondrial function to regulate cellular chemistry by metabolism. The mammalian MCS comprises the transporters of the 53-member canonical SLC25A family and a lesser number of identified noncanonical transporters. The recent discovery and investigations of the mitochondrial pyruvate carrier (MPC) illustrate the diverse effects a single mitochondrial carrier may exert on cellular function. However, the transport selectivities of many carriers remain unknown, and most have not been functionally investigated in mammalian cells. The mechanisms coordinating their function as a unified system remain undefined. Increased accessibility to molecular genetic and metabolomic technologies now greatly enables investigation of the MCS. Continued investigation of the MCS may reveal how mitochondria encode complex regulatory information within chemical thermodynamic gradients. This understanding may enable precision modulation of cellular chemistry to counteract the dysmetabolism inherent in disease.
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Affiliation(s)
- Eric B Taylor
- Department of Biochemistry, Fraternal Order of the Eagles Diabetes Center, Holden Comprehensive Cancer Center, Abboud Cardiovascular Research Center, Pappajohn Biomedical Discovery Institute, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA.
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41
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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.
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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
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42
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Mugabo Y, Zhao S, Lamontagne J, Al-Mass A, Peyot ML, Corkey BE, Joly E, Madiraju SRM, Prentki M. Metabolic fate of glucose and candidate signaling and excess-fuel detoxification pathways in pancreatic β-cells. J Biol Chem 2017; 292:7407-7422. [PMID: 28280244 DOI: 10.1074/jbc.m116.763060] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 03/06/2017] [Indexed: 12/28/2022] Open
Abstract
Glucose metabolism promotes insulin secretion in β-cells via metabolic coupling factors that are incompletely defined. Moreover, chronically elevated glucose causes β-cell dysfunction, but little is known about how cells handle excess fuels to avoid toxicity. Here we sought to determine which among the candidate pathways and coupling factors best correlates with glucose-stimulated insulin secretion (GSIS), define the fate of glucose in the β-cell, and identify pathways possibly involved in excess-fuel detoxification. We exposed isolated rat islets for 1 h to increasing glucose concentrations and measured various pathways and metabolites. Glucose oxidation, oxygen consumption, and ATP production correlated well with GSIS and saturated at 16 mm glucose. However, glucose utilization, glycerol release, triglyceride and glycogen contents, free fatty acid (FFA) content and release, and cholesterol and cholesterol esters increased linearly up to 25 mm glucose. Besides being oxidized, glucose was mainly metabolized via glycerol production and release and lipid synthesis (particularly FFA, triglycerides, and cholesterol), whereas glycogen production was comparatively low. Using targeted metabolomics in INS-1(832/13) cells, we found that several metabolites correlated well with GSIS, in particular some Krebs cycle intermediates, malonyl-CoA, and lower ADP levels. Glucose dose-dependently increased the dihydroxyacetone phosphate/glycerol 3-phosphate ratio in INS-1(832/13) cells, indicating a more oxidized state of NAD in the cytosol upon glucose stimulation. Overall, the data support a role for accelerated oxidative mitochondrial metabolism, anaplerosis, and malonyl-CoA/lipid signaling in β-cell metabolic signaling and suggest that a decrease in ADP levels is important in GSIS. The results also suggest that excess-fuel detoxification pathways in β-cells possibly comprise glycerol and FFA formation and release extracellularly and the diversion of glucose carbons to triglycerides and cholesterol esters.
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Affiliation(s)
- Yves Mugabo
- From the Montreal Diabetes Research Center and Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, Québec H2X 0A9, Canada.,Departments of Nutrition, Biochemistry and Molecular Medicine, Faculty of Medicine, University of Montréal, Montreal, Québec H3C 3J7, Canada, and
| | - Shangang Zhao
- From the Montreal Diabetes Research Center and Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, Québec H2X 0A9, Canada.,Departments of Medicine and Human Genetics, McGill University, Montreal, Québec H3A 1B1, Canada
| | - Julien Lamontagne
- From the Montreal Diabetes Research Center and Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, Québec H2X 0A9, Canada
| | - Anfal Al-Mass
- From the Montreal Diabetes Research Center and Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, Québec H2X 0A9, Canada.,Departments of Medicine and Human Genetics, McGill University, Montreal, Québec H3A 1B1, Canada
| | - Marie-Line Peyot
- From the Montreal Diabetes Research Center and Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, Québec H2X 0A9, Canada
| | - Barbara E Corkey
- Department of Medicine, Obesity Research Center, Boston University School of Medicine, Boston, Massachusetts 02118
| | - Erik Joly
- From the Montreal Diabetes Research Center and Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, Québec H2X 0A9, Canada
| | - S R Murthy Madiraju
- From the Montreal Diabetes Research Center and Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, Québec H2X 0A9, Canada
| | - Marc Prentki
- From the Montreal Diabetes Research Center and Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, Québec H2X 0A9, Canada, .,Departments of Nutrition, Biochemistry and Molecular Medicine, Faculty of Medicine, University of Montréal, Montreal, Québec H3C 3J7, Canada, and
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43
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Morten KJ, Potter M, Badder L, Sivathondan P, Dragovic R, Neumann A, Gavin J, Shrestha R, Reilly S, Phadwal K, Lodge TA, Borzychowski A, Cookson S, Mitchell C, Morovat A, Simon AK, Uusimaa J, Hynes J, Poulton J. Insights into pancreatic β cell energy metabolism using rodent β cell models. Wellcome Open Res 2017; 2:14. [DOI: 10.12688/wellcomeopenres.10535.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/10/2017] [Indexed: 11/20/2022] Open
Abstract
Background:Mitochondrial diabetes is primarily caused by β-cell failure, but there are gaps in our understanding of pathogenesis.Methods:By reducing glucose, we induced energetic stress in two rodent β-cell models to assess effects on cellular function.Results:Culturing rat insulin-secreting INS-1 cells in low glucose conditions caused a rapid reduction in whole cell respiration, associated with elevated mitochondrial reactive oxygen species production, and an altered glucose-stimulated insulin secretion profile. Prolonged exposure to reduced glucose directly impaired mitochondrial function and reduced autophagy.Conclusions:Insulinoma cell lines provide a useful model of mechanisms affecting β-cell mitochondrial function or studying mitochondrial associated drug toxicity.
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44
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Ahmad F, Zhou Y. Pitfalls and Challenges in Nanotoxicology: A Case of Cobalt Ferrite (CoFe 2O 4) Nanocomposites. Chem Res Toxicol 2017; 30:492-507. [PMID: 28118545 DOI: 10.1021/acs.chemrestox.6b00377] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Nanotechnology is developing at a rapid pace with promises of a brilliant socio-economic future. The apprehensions of vivid future involvement with nanotechnology make nanoobjects ubiquitous in the macroscopic world of humans. Nanotechnology helps us to visualize the new mysterious horizons in engineering, sophisticated electronics, environmental remediation, biosensing, and nanomedicine. In all these hotspots, cobalt ferrite (CoFe) nanoparticles (NPs) are outstanding contestants because of their astonishing controllable physicochemical and magnetic properties with ease of synthesis methods. The extensive use of CoFe NPs may result in CoFe NPs easily penetrating the human body unintentionally by ingestion, inhalation, adsorption, etc. and intentionally being instilled into the human body during biomedical diagnostics and treatment. After being housed in the human body, it might induce oxidative stress, cytotoxicity, genotoxicity, inflammation, apoptosis, and developmental, metabolic and hormonal abnormalities. In this review, we compiled the toxicity knowledge of CoFe NPs aimed to provide the safe usage of this breed of nanomaterials.
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Affiliation(s)
- Farooq Ahmad
- College of Chemical Engineering, Zhejiang University of Technology , Hangzhou 310032, China.,State Key Laboratory of Metal Matrix Composites, School of Material Science and Engineering, Shanghai Jiao Tong University , 800 Dongchuan Road, Shanghai 200240, China
| | - Ying Zhou
- College of Chemical Engineering, Zhejiang University of Technology , Hangzhou 310032, China.,Research Center of Analysis and Measurement, Zhejiang University of Technology , 18 Chaowang Road, Hangzhou 310032, China
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45
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de Souza AH, Santos LRB, Roma LP, Bensellam M, Carpinelli AR, Jonas JC. NADPH oxidase-2 does not contribute to β-cell glucotoxicity in cultured pancreatic islets from C57BL/6J mice. Mol Cell Endocrinol 2017; 439:354-362. [PMID: 27664519 DOI: 10.1016/j.mce.2016.09.022] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 08/24/2016] [Accepted: 09/20/2016] [Indexed: 11/20/2022]
Abstract
High glucose-induced oxidative stress and increased NADPH oxidase-2 (NOX2) activity may contribute to the progressive decline of the functional β-cell mass in type 2 diabetes. To test that hypothesis, we characterized, in islets from male NOX2 knockout (NOX2-KO) and wild-type (WT) C57BL/6J mice cultured for up to 3 weeks at 10 or 30 mmol/l glucose (G10 or G30), the in vitro effects of glucose on cytosolic oxidative stress using probes sensing glutathione oxidation (GRX1-roGFP2), thiol oxidation (roGFP1) or H2O2 (roGFP2-Orp1), on β-cell stimulus-secretion coupling events and on β-cell apoptosis. After 1-2 days of culture in G10, the glucose stimulation of insulin secretion (GSIS) was ∼1.7-fold higher in NOX2-KO vs. WT islets at 20-30 mmol/l glucose despite similar rises in NAD(P)H and intracellular calcium concentration ([Ca2+]i) and no differences in cytosolic GRX1-roGFP2 oxidation. After long-term culture at G10, roGFP1 and roGFP2-Orp1 oxidation and β-cell apoptosis remained low, and the glucose-induced rises in NAD(P)H, [Ca2+]i and GSIS were similarly preserved in both islet types. After prolonged culture at G30, roGFP1 and roGFP2-Orp1 oxidation increased in parallel with β-cell apoptosis, the glucose sensitivity of the NADPH, [Ca2+]i and insulin secretion responses increased, the maximal [Ca2+]i response decreased, but maximal GSIS was preserved. These responses were almost identical in both islet types. In conclusion, NOX2 is a negative regulator of maximal GSIS in C57BL/6J mouse islets, but it does not detectably contribute to the in vitro glucotoxic induction of cytosolic oxidative stress and alterations of β-cell survival and function.
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Affiliation(s)
- Arnaldo H de Souza
- Université catholique de Louvain, Institute of Experimental and Clinical Research, Pole of Endocrinology, Diabetes and Nutrition, Brussels, Belgium; Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Laila R B Santos
- Université catholique de Louvain, Institute of Experimental and Clinical Research, Pole of Endocrinology, Diabetes and Nutrition, Brussels, Belgium
| | - Leticia P Roma
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Mohammed Bensellam
- Université catholique de Louvain, Institute of Experimental and Clinical Research, Pole of Endocrinology, Diabetes and Nutrition, Brussels, Belgium
| | - Angelo R Carpinelli
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Jean-Christophe Jonas
- Université catholique de Louvain, Institute of Experimental and Clinical Research, Pole of Endocrinology, Diabetes and Nutrition, Brussels, Belgium.
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46
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Phannasil P, Ansari IUH, El Azzouny M, Longacre MJ, Rattanapornsompong K, Burant CF, MacDonald MJ, Jitrapakdee S. Mass spectrometry analysis shows the biosynthetic pathways supported by pyruvate carboxylase in highly invasive breast cancer cells. Biochim Biophys Acta Mol Basis Dis 2016; 1863:537-551. [PMID: 27890529 DOI: 10.1016/j.bbadis.2016.11.021] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 10/28/2016] [Accepted: 11/22/2016] [Indexed: 12/22/2022]
Abstract
We recently showed that the anaplerotic enzyme pyruvate carboxylase (PC) is up-regulated in human breast cancer tissue and its expression is correlated with the late stages of breast cancer and tumor size [Phannasil et al., PloS One 10, e0129848, 2015]. In the current study we showed that PC enzyme activity is much higher in the highly invasive breast cancer cell line MDA-MB-231 than in less invasive breast cancer cell lines. We generated multiple stable PC knockdown cell lines from the MDA-MB-231 cell line and used mass spectrometry with 13C6-glucose and 13C5-glutamine to discern the pathways that use PC in support of cell growth. Cells with severe PC knockdown showed a marked reduction in viability and proliferation rates suggesting the perturbation of pathways that are involved in cancer invasiveness. Strong PC suppression lowered glucose incorporation into downstream metabolites of oxaloacetate, the product of the PC reaction, including malate, citrate and aspartate. Levels of pyruvate, lactate, the redox partner of pyruvate, and acetyl-CoA were also lower suggesting the impairment of mitochondrial pyruvate cycles. Serine, glycine and 5-carbon sugar levels and flux of glucose into fatty acids were decreased. ATP, ADP and NAD(H) levels were unchanged indicating that PC suppression did not significantly affect mitochondrial energy production. The data indicate that the major metabolic roles of PC in invasive breast cancer are primarily anaplerosis, pyruvate cycling and mitochondrial biosynthesis of precursors of cellular components required for breast cancer cell growth and replication.
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Affiliation(s)
- Phatchariya Phannasil
- Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Israr-Ul H Ansari
- Childrens Diabetes Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Mahmoud El Azzouny
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Melissa J Longacre
- Childrens Diabetes Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | | | - Charles F Burant
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Michael J MacDonald
- Childrens Diabetes Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Sarawut Jitrapakdee
- Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, Thailand.
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47
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Pizarro-Delgado J, Deeney JT, Corkey BE, Tamarit-Rodriguez J. Direct Stimulation of Islet Insulin Secretion by Glycolytic and Mitochondrial Metabolites in KCl-Depolarized Islets. PLoS One 2016; 11:e0166111. [PMID: 27851770 PMCID: PMC5112877 DOI: 10.1371/journal.pone.0166111] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 10/24/2016] [Indexed: 11/26/2022] Open
Abstract
We have previously demonstrated that islet depolarization with 70 mM KCl opens Cx36 hemichannels and allows diffusion of small metabolites and cofactors through the β-cell plasma membrane. We have investigated in this islet “permeabilized” model whether glycolytic and citric acid cycle intermediates stimulate insulin secretion and how it correlates with ATP production (islet content plus extracellular nucleotide accumulation). Glycolytic intermediates (10 mM) stimulated insulin secretion and ATP production similarly. However, they showed differential sensitivities to respiratory chain or enzyme inhibitors. Pyruvate showed a lower secretory capacity and less ATP production than phosphoenolpyruvate, implicating an important role for glycolytic generation of ATP. ATP production by glucose-6-phosphate was not sensitive to a pyruvate kinase inhibitor that effectively suppressed the phosphoenolpyruvate-induced secretory response and islet ATP rise. Strong suppression of both insulin secretion and ATP production induced by glucose-6-phosphate was caused by 10 μM antimycin A, implicating an important role for the glycerophosphate shuttle in transferring reducing equivalents to the mitochondria. Five citric acid cycle intermediates were investigated for their secretory and ATP production capacity (succinate, fumarate, malate, isocitrate and α-ketoglutarate at 5 mM, together with ADP and/or NADP+ to feed the NADPH re-oxidation cycles). The magnitude of the secretory response was very similar among the different mitochondrial metabolites but α-ketoglutarate showed a more sustained second phase of secretion. Gabaculine (1 mM, a GABA-transaminase inhibitor) suppressed the second phase of secretion and the ATP-production stimulated by α-ketoglutarate, supporting a role for the GABA shuttle in the control of glucose-induced insulin secretion. None of the other citric acid intermediates essayed showed any suppression of both insulin secretion or ATP-production by the presence of gabaculine. We propose that endogenous GABA metabolism in the “GABA-shunt” facilitates ATP production in the citric acid cycle for an optimal insulin secretion.
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Affiliation(s)
- Javier Pizarro-Delgado
- Obesity Research Center, Department of Medicine, Boston University School of Medicine, Boston, MA, United States of America
- Biochemistry Department, Medical School, Complutense University, Madrid, Spain
| | - Jude T. Deeney
- Obesity Research Center, Department of Medicine, Boston University School of Medicine, Boston, MA, United States of America
| | - Barbara E. Corkey
- Obesity Research Center, Department of Medicine, Boston University School of Medicine, Boston, MA, United States of America
| | - Jorge Tamarit-Rodriguez
- Obesity Research Center, Department of Medicine, Boston University School of Medicine, Boston, MA, United States of America
- Biochemistry Department, Medical School, Complutense University, Madrid, Spain
- * E-mail:
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48
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Accili D, Talchai SC, Kim-Muller JY, Cinti F, Ishida E, Ordelheide AM, Kuo T, Fan J, Son J. When β-cells fail: lessons from dedifferentiation. Diabetes Obes Metab 2016; 18 Suppl 1:117-22. [PMID: 27615140 PMCID: PMC5021187 DOI: 10.1111/dom.12723] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2016] [Accepted: 05/03/2016] [Indexed: 12/14/2022]
Abstract
Diabetes is caused by a combination of impaired responsiveness to insulin and reduced production of insulin by the pancreas. Until recently, the decline of insulin production had been ascribed to β-cell death. But recent research has shown that β-cells do not die in diabetes, but undergo a silencing process, termed "dedifferentiation." The main implication of this discovery is that β-cells can be revived by appropriate treatments. We have shown that mitochondrial abnormalities are a key step in the progression of β-cell dysfunction towards dedifferentiation. In normal β-cells, mitochondria generate energy required to sustain insulin production and its finely timed release in response to the body's nutritional status. A normal β-cell can adapt its mitochondrial fuel source based on substrate availability, a concept known as "metabolic flexibility." This capability is the first casualty in the progress of β-cell failure. β-Cells lose the ability to select the right fuel for mitochondrial energy production. Mitochondria become overloaded, and accumulate by-products derived from incomplete fuel utilization. Energy production stalls, and insulin production drops, setting the stage for dedifferentiation. The ultimate goal of these investigations is to explore novel treatment paradigms that will benefit people with diabetes.
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Affiliation(s)
- D Accili
- Department of Medicine and Berrie Diabetes Center, Columbia University, New York, New York.
| | - S C Talchai
- Department of Medicine and Berrie Diabetes Center, Columbia University, New York, New York
| | - J Y Kim-Muller
- Department of Medicine and Berrie Diabetes Center, Columbia University, New York, New York
| | - F Cinti
- Department of Medicine and Berrie Diabetes Center, Columbia University, New York, New York
| | - E Ishida
- Department of Medicine and Berrie Diabetes Center, Columbia University, New York, New York
| | - A M Ordelheide
- Department of Medicine and Berrie Diabetes Center, Columbia University, New York, New York
| | - T Kuo
- Department of Medicine and Berrie Diabetes Center, Columbia University, New York, New York
| | - J Fan
- Department of Medicine and Berrie Diabetes Center, Columbia University, New York, New York
| | - J Son
- Department of Medicine and Berrie Diabetes Center, Columbia University, New York, New York
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49
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Serrano-Contreras JI, García-Pérez I, Meléndez-Camargo ME, Zepeda LG. NMR-Based Metabonomic Analysis of Physiological Responses to Starvation and Refeeding in the Rat. J Proteome Res 2016; 15:3241-54. [PMID: 27518853 DOI: 10.1021/acs.jproteome.6b00433] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Starvation is a postabsorptive condition derived from a limitation on food resources by external factors. Energy homeostasis is maintained under this condition by using sources other than glucose via adaptive mechanisms. After refeeding, when food is available, other adaptive processes are linked to energy balance. However, less has been reported about the physiological mechanisms present as a result of these conditions, considering the rat as a supraorganism. Metabolic profiling using (1)H nuclear magnetic resonance spectroscopy was used to characterize the physiological metabolic differences in urine specimens collected under starved, refed, and recovered conditions. In addition, because starvation induced lack of faecal production and not all animals produced faeces during refeeding, 24 h pooled faecal water samples were also analyzed. Urinary metabolites upregulated by starvation included 2-butanamidoacetate, 3-hydroxyisovalerate, ketoleucine, methylmalonate, p-cresyl glucuronide, p-cresyl sulfate, phenylacetylglycine, pseudouridine, creatinine, taurine, and N-acetyl glycoprotein, which were related to renal and skeletal muscle function, β-oxidation, turnover of proteins and RNA, and host-microbial interactions. Food-derived metabolites, including gut microbial cometabolites, and tricarboxylic acid cycle intermediates were upregulated under refed and recovered conditions, which characterized anabolic urinary metabotypes. The upregulation of creatine and pantothenate indicated an absorptive state after refeeding. Fecal short chain fatty acids, 3-(3-hydroxyphenyl)propionate, lactate, and acetoin provided additional information about the combinatorial metabolism between the host and gut microbiota. This investigation contributes to allow a deeper understanding of physiological responses associated with starvation and refeeding.
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Affiliation(s)
- José I Serrano-Contreras
- Departamento de Química Orgánica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional , Prolongación de Carpio y Plan de Ayala s/n, Col. Santo Tomas, C.P. 11340 Delegación Miguel Hidalgo, Ciudad de México, México.,Departamento de Farmacia, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional , Av. Wilfrido Massieu, Esq. Cda. Miguel Stampa s/n, Unidad Profesional Adolfo López Mateos, C.P. 07738 Delegación Gustavo A. Madero, Ciudad de México, México
| | - Isabel García-Pérez
- Computational and Systems Medicine, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London , London SW7 2AZ, United Kingdom
| | - María E Meléndez-Camargo
- Departamento de Farmacia, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional , Av. Wilfrido Massieu, Esq. Cda. Miguel Stampa s/n, Unidad Profesional Adolfo López Mateos, C.P. 07738 Delegación Gustavo A. Madero, Ciudad de México, México
| | - L Gerardo Zepeda
- Departamento de Química Orgánica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional , Prolongación de Carpio y Plan de Ayala s/n, Col. Santo Tomas, C.P. 11340 Delegación Miguel Hidalgo, Ciudad de México, México
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50
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El Azzouny M, Longacre MJ, Ansari IUH, Kennedy RT, Burant CF, MacDonald MJ. Knockdown of ATP citrate lyase in pancreatic beta cells does not inhibit insulin secretion or glucose flux and implicates the acetoacetate pathway in insulin secretion. Mol Metab 2016; 5:980-987. [PMID: 27689010 PMCID: PMC5034614 DOI: 10.1016/j.molmet.2016.07.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 07/21/2016] [Accepted: 07/27/2016] [Indexed: 12/31/2022] Open
Abstract
Objective Glucose-stimulated insulin secretion in pancreatic beta cells requires metabolic signals including the generation of glucose-derived short chain acyl-CoAs in the cytosol from mitochondrially-derived metabolites. One concept of insulin secretion is that ATP citrate lyase generates short chain acyl-CoAs in the cytosol from mitochondrially-derived citrate. Of these, malonyl-CoA, is believed to be an important signal in insulin secretion. Malonyl-CoA is also a precursor for lipids. Our recent evidence suggested that, in the mitochondria of beta cells, glucose-derived pyruvate can be metabolized to acetoacetate that is exported to the cytosol and metabolized to the same short chain acyl-CoAs and fatty acids that can be derived from citrate. We tested for redundancy of the citrate pathway. Methods We inhibited ATP citrate lyase activity using hydroxycitrate as well as studying a stable cell line generated with shRNA knockdown of ATP citrate lyase in the pancreatic beta cell line INS-1 832/13. Results In both instances glucose-stimulated insulin release was not inhibited. Mass spectrometry analysis showed that the flux of carbon from [U-13C]glucose and/or [U-13C]α-ketoisocaproic acid (KIC) into short chain acyl-CoAs in cells with hydroxycitrate-inhibited ATP citrate lyase or in the cell line with stable severe (>90%) shRNA knockdown of ATP citrate lyase was similar to the controls. Both 13C-glucose and 13C-KIC introduced substantial 13C labeling into acetyl-CoA, malonyl-CoA, and HMG-CoA under both conditions. Glucose flux into fatty acids was not affected by ATP citrate lyase knockdown. Conclusion The results establish the involvement of the acetoacetate pathway in insulin secretion in pancreatic beta cells. In pancreatic beta cells mitochondria synthesize metabolites from glucose. Mitochondria-derived citrate and acetoacetate can transfer carbon to the cytosol. The citrate pathway requires ATP citrate lyase (ACLY). Inhibition of ACLY did not stop metabolite export to the cytosol or insulin release. The results establish the role of the acetoacetate pathway in insulin secretion.
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Affiliation(s)
- Mahmoud El Azzouny
- Metabolism, Endocrinology and Diabetes, University of Michigan Medical School, Ann Arbor, MI 48109, United States
| | - Melissa J Longacre
- Childrens Diabetes Center, University of Wisconsin School of Medicine and Public Health, Madison, WI 53706, United States
| | - Israr-Ul H Ansari
- Childrens Diabetes Center, University of Wisconsin School of Medicine and Public Health, Madison, WI 53706, United States
| | - Robert T Kennedy
- Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109, United States
| | - Charles F Burant
- Metabolism, Endocrinology and Diabetes, University of Michigan Medical School, Ann Arbor, MI 48109, United States
| | - Michael J MacDonald
- Childrens Diabetes Center, University of Wisconsin School of Medicine and Public Health, Madison, WI 53706, United States.
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