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Hals I, Ma Z, Kylling M, Bjørkvik A, Zhao A, Catrina SB, Zhang X, Björklund A, Grill V. Time dynamics of elevated glucose and beta-hydroxybutyrate on beta cell mitochondrial metabolism. Islets 2025; 17:2503515. [PMID: 40387167 PMCID: PMC12091920 DOI: 10.1080/19382014.2025.2503515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2024] [Revised: 04/14/2025] [Accepted: 04/29/2025] [Indexed: 05/20/2025] Open
Abstract
Chronic hyperglycemia impairs mitochondrial function of beta cells. Changes in mitochondrial function preceding a negative glucose effect have not been fully characterized, nor interactions with ketones. To compare effects on beta cell mitochondrial function by short and longer exposures to elevated glucose and interactions with ketones oxygen consumption rate (OCR) was measured in intact clonal beta cells by an OROBOROS and in rat islets by a Seahorse instrument. Proteins (subunits) of mitochondrial complexes (C) were measured by immunoblotting. ATP and ROS were measured in islets. In INS-1 832/13 cells, overnight exposure to 27 vs. 11 mm glucose increased OCR and uncoupled mitochondrial respiration. These effects vanished when prolonging the exposure time of elevated glucose. C1 was decreased after two days of culture with high glucose. Interactions with racemic 5 and 20 mm beta-hydroxybutyrate (BHB) were not detected. In islets, culture overnight at 27 vs.11 mm glucose enhanced basal OCR. No decrease in glucose-induced OCR was seen after prolonging 27 mm glucose for two days. Interactions with 5 mm BHB were not detected. Prolonged exposure to 27 mm glucose enhanced basal ECAR (extracellular acidification rate) and an ECAR response to acute elevation of glucose. C1 and 3 and 4 were decreased after two days of 27 vs. 11 mm glucose. ATP levels were decreased at this time-point and extracellular ROS increased. High glucose time-dependently affects mitochondrial function in clonal beta cells and islets. C1 was uniformly decreased. Interactions with BHB were not detected.
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Affiliation(s)
- Ik Hals
- Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
- Department of Research, Nord-Trøndelag Hospital Trust, Levanger, Norway
| | - Z. Ma
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
| | - M. Kylling
- Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - A. Bjørkvik
- Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - A. Zhao
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
| | - S-B. Catrina
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
- Academic Specialist Center, Center for Diabetes, Stockholm, Sweden
| | - X. Zhang
- Department of Research, Nord-Trøndelag Hospital Trust, Levanger, Norway
| | - A. Björklund
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
- Academic Specialist Center, Center for Diabetes, Stockholm, Sweden
| | - V. Grill
- Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
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2
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Lin KA, Su CC, Liu SH, Lee KI, Fang KM, Tang CH, Kuo CY, Chang KC, Ke JA, Huang CF, Chen YW, Yang CY. Antimony induces mitochondria-dependent and ER stress-triggered apoptosis via the oxidative stress-activated JNK signaling pathway in pancreatic islet β-cells. Toxicology 2025; 516:154188. [PMID: 40368022 DOI: 10.1016/j.tox.2025.154188] [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: 02/17/2025] [Revised: 04/30/2025] [Accepted: 05/11/2025] [Indexed: 05/16/2025]
Abstract
Antimony (Sb), a silvery-white metal, is a heavy metal of particular prevalence that has the ability to result in adverse effects in humans through environmental exposure resulting from natural processes and human activities. Epidemiological studies have suggested that Sb has an association with the potential for diabetes mellitus (DM) development. However, the mechanisms by which Sb exerts toxicological effects on pancreatic islet β-cells are still not clear. In this investigation, Sb exposure significantly inhibited rat pancreatic islet β-cell-derived RIN-m5F cell viability and insulin secretion, while inducing mitochondria-dependent apoptotic signals, inclusive of increased apoptotic cell populations, caspase-3 activity, the expression of PARP and caspase-3/-7/-9, and mitochondrial dysfunction. RIN-m5F cells exposure to Sb also led to the triggering of endoplasmic reticulum (ER) stress via the induction of a number of vital molecules, including CHOP, XBP-1s, and caspase-12. In Sb-exposed RIN-m5F cells, 4-PBA pretreatment (an inhibitor of ER stress) significantly suppressed protein expression related to ER stress and events of an apoptotic nature. Furthermore, exposure to Sb resulted in the significant activation of AMPKα, ERK1/2, and JNK signaling, as well as reactive oxygen species (ROS) generation. Pretreatment with SP600125 (an inhibitor of JNK) and antioxidant NAC, but not PD98059 (an inhibitor of ERK) or compound C (an inhibitor of AMPK), effectively abrogated the cytotoxicity, ER stress responses, mitochondrial dysfunction, apoptotic events, insulin secretion inhibition, and JNK activation in Sb-exposed rat pancreatic islet β-cells. However, SP600125 did not prevent ROS generation, which was inhibited by the antioxidant NAC. Collectively, the results demonstrate exposure to Sb to exert β-cell cytotoxicity through oxidative stress-activated JNK signaling downstream-regulated mitochondria-dependent and ER stress-triggered cell apoptotic pathways, eventually resulting in the death of rat pancreatic islet β-cells.
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Affiliation(s)
- Ken-An Lin
- Graduate Institute of Biomedical Sciences, College of Medicine, China Medical University, Taichung 404, Taiwan
| | - Chin-Chuan Su
- Department of Otorhinolaryngology, Head and Neck Surgery, Changhua Christian Hospital, Changhua County, Changhua County 500, Taiwan; Department of Post-Baccalaureate Medicine, College of Medicine, National Chung Hsing University, Taichung 402, Taiwan
| | - Shing-Hwa Liu
- Institute of Toxicology, College of Medicine, National Taiwan University, Taipei 100, Taiwan
| | - Kuan-I Lee
- Department of Emergency, Taichung Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Taichung 427, Taiwan
| | - Kai-Min Fang
- Department of Otolaryngology, Far Eastern Memorial Hospital, New Taipei City 220, Taiwan
| | - Chih-Hsin Tang
- Graduate Institute of Biomedical Sciences, College of Medicine, China Medical University, Taichung 404, Taiwan
| | - Chun-Ying Kuo
- Department of Otorhinolaryngology, Head and Neck Surgery, Changhua Christian Hospital, Changhua County, Changhua County 500, Taiwan
| | - Kai-Chih Chang
- Center for Digestive Medicine, Department of Internal Medicine, China Medical University Hospital, Taichung 404, Taiwan
| | - Jun-An Ke
- Department of Medical Education, Changhua Christian Hospital Changhua City 500, Taiwan
| | - Chun-Fa Huang
- School of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung 404, Taiwan; Department of Nursing, College of Medical and Health Science, Asia University, Taichung 413, Taiwan
| | - Ya-Wen Chen
- Department of Physiology, School of Medicine, College of Medicine, China Medical University, Taichung 404, Taiwan.
| | - Ching-Yao Yang
- Department of Surgery, College of Medicine, National Taiwan University, Taipei 100, Taiwan; Department of Surgery, National Taiwan University Hospital, Taipei 100, Taiwan.
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Naatz A, Bohl KS, Jones Lipinski RA, Nord JA, Gehant AL, Hansen PA, Smith BC, Corbett JA. Role of SIRT3 in the regulation of Gadd45α expression and DNA repair in β-cells. J Biol Chem 2025; 301:108451. [PMID: 40147772 PMCID: PMC12051128 DOI: 10.1016/j.jbc.2025.108451] [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: 10/21/2024] [Revised: 03/09/2025] [Accepted: 03/22/2025] [Indexed: 03/29/2025] Open
Abstract
In previous studies, we have shown that growth arrest and DNA damage (Gadd) 45α is required for the repair of nitric oxide-mediated DNA damage in β-cells. Gadd45α expression is stimulated by nitric oxide and requires forkhead box protein (Fox) O1 and NAD+-dependent deacetylase activity. Based on inhibitor studies, we attributed this activity to Sirtuin (SIRT)1; however, the inhibitors used in this previous study also attenuate the deacetylase activity of SIRT2, 3, and 6. We now provide experimental evidence that SIRT1 is dispensable for β-cell expression of Gadd45α and that the mitochondrial localized isoform SIRT3, is required for DNA repair in β-cells. We show that siRNA knockdown of Sirt3 attenuates nitric oxide-stimulated Gadd45α mRNA accumulation in both wildtype and Sirt1-/- INS 832/13 cells as well as isolated rat islets and that SIRT3 inhibition increases FoxO1 acetylation and attenuates DNA repair in response to nitric oxide. While SIRT3 is predominantly localized to mitochondria, a small fraction is localized in the nucleus of insulin-containing cells and functions to participate in the regulation of FoxO1-dependent, nitric oxide-stimulated DNA repair.
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Affiliation(s)
- Aaron Naatz
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Kelsey S Bohl
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | | | - Joshua A Nord
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Alyssa L Gehant
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Polly A Hansen
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Brian C Smith
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - John A Corbett
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.
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Tamarit-Rodriguez J. Stimulus-Secretion Coupling Mechanisms of Glucose-Induced Insulin Secretion: Biochemical Discrepancies Among the Canonical, ADP Privation, and GABA-Shunt Models. Int J Mol Sci 2025; 26:2947. [PMID: 40243540 PMCID: PMC11989153 DOI: 10.3390/ijms26072947] [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: 12/28/2024] [Revised: 02/26/2025] [Accepted: 03/20/2025] [Indexed: 04/18/2025] Open
Abstract
Integration of old and recent experimental data consequences is needed to correct and help improve the hypothetical mechanism responsible for the stimulus-secretion coupling mechanism of glucose-induced insulin secretion. The main purpose of this review is to supply biochemical considerations about some of the metabolic pathways implicated in the process of insulin secretion. It is emphasized that glucose β-cells' threshold to activate secretion (5 mM) might depend on the predominance of anaerobic glycolysis at this basal glucose concentration. This argues against the predominance of phosphoenolpyruvate (PEP) over mitochondrial pyruvate oxidation for the initiation of insulin secretion. Full quantitative and qualitative reproduction, except the threshold effect, of glucose-induced insulin release by a permeable methylated analog of succinic acid indicates that mitochondrial metabolism is enough for sustained insulin secretion. Mitochondrial PEP generation is skipped if the GABA-shunt pathway is exclusively coupled to the citric acid cycle, as proposed in the "GABA-shunt" model of stimulus-secretion coupling. Strong or maintained depolarization by KCl or sulfonylureas might induce the opening of β-cells Cx36 hemichannels, allowing the loss of adenine nucleotides and other metabolites, mimicking the effect of an excessive mitochondrial ATP demand. A few alterations of OxPhos (Oxidative Phosphorylation) regulation in human T2D islets have been described, but the responsible mechanism(s) is (are) not yet known. Finally, some experimental data arguing as proof of the relative irrelevance of the mitochondrial function in the insulin secretion coupling mechanism for the initiation and/or sustained stimulation of hormone release are discussed.
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Tu JJ, Ye C, Teng XY, Zang YY, Sun XY, Chen S, Chen J, Shi YS. Osmosensor TMEM63B facilitates insulin secretion in pancreatic β-cells. SCIENCE CHINA. LIFE SCIENCES 2025:10.1007/s11427-024-2833-3. [PMID: 39985646 DOI: 10.1007/s11427-024-2833-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2024] [Accepted: 12/30/2024] [Indexed: 02/24/2025]
Abstract
Elevated glucose metabolism triggers two primary processes that lead to β-cell depolarization and insulin secretion: the closure of ATP-sensitive K+ channels via ATP-dependent mechanisms and the activation of mechanosensitive channels (MSCs) due to cell swelling. However, the identity of these MSCs remains unclear. In this study, we found that TMEM63B is a stretch-activated cation channel (SAC) crucial for regulating insulin secretion in response to elevated glucose levels. TMEM63B is abundantly expressed in β-cells, and its deletion impairs insulin secretion triggered by high glucose. High glucose levels typically increase Ca2+ influx and firing frequency in β-cells, a response largely eliminated when TMEM63B is deleted. Mechanistically, glucose metabolism induces cell swelling and activates TMEM63B, which, in turn, leads to β-cell depolarization and insulin secretion. In conclusion, our findings demonstrate that TMEM63B is an SAC essential for regulating insulin secretion in response to elevated glucose levels.
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Affiliation(s)
- Jing-Jing Tu
- Department of Anesthesiology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, 210008, China
- Guangdong Institute of Intelligence Science and Technology, Zhuhai, 519031, China
- Ministry of Education Key Laboratory of Model Animal for Disease Study, Jiangsu Key Laboratory of Molecular Medicine, Model Animal Research Center, Medical School, Nanjing University, Nanjing, 210032, China
| | - Chang Ye
- Department of Anesthesiology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, 210008, China
- Ministry of Education Key Laboratory of Model Animal for Disease Study, Jiangsu Key Laboratory of Molecular Medicine, Model Animal Research Center, Medical School, Nanjing University, Nanjing, 210032, China
| | - Xiao-Yu Teng
- Guangdong Institute of Intelligence Science and Technology, Zhuhai, 519031, China
| | - Yan-Yu Zang
- Ministry of Education Key Laboratory of Model Animal for Disease Study, Jiangsu Key Laboratory of Molecular Medicine, Model Animal Research Center, Medical School, Nanjing University, Nanjing, 210032, China
| | - Xiao-Ye Sun
- Department of Hepatology and Gastroenterology, Tianjin First Central Hospital, Tianjin, 300192, China
| | - Shuai Chen
- Ministry of Education Key Laboratory of Model Animal for Disease Study, Jiangsu Key Laboratory of Molecular Medicine, Model Animal Research Center, Medical School, Nanjing University, Nanjing, 210032, China.
| | - Jiang Chen
- Department of Neurology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, 210008, China.
| | - Yun Stone Shi
- Department of Anesthesiology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, 210008, China.
- Guangdong Institute of Intelligence Science and Technology, Zhuhai, 519031, China.
- Ministry of Education Key Laboratory of Model Animal for Disease Study, Jiangsu Key Laboratory of Molecular Medicine, Model Animal Research Center, Medical School, Nanjing University, Nanjing, 210032, China.
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Capuani S, Campa‐Carranza JN, Hernandez N, Chua CYX, Grattoni A. Modeling of a Bioengineered Immunomodulating Microenvironment for Cell Therapy. Adv Healthc Mater 2025; 14:e2304003. [PMID: 38215451 PMCID: PMC11239796 DOI: 10.1002/adhm.202304003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Indexed: 01/14/2024]
Abstract
Cell delivery and encapsulation platforms are under development for the treatment of Type 1 Diabetes among other diseases. For effective cell engraftment, these platforms require establishing an immune-protected microenvironment as well as adequate vascularization and oxygen supply to meet the metabolic demands of the therapeutic cells. Current platforms rely on 1) immune isolating barriers and indirect vascularization or 2) direct vascularization with local or systemic delivery of immune modulatory molecules. Supported by experimental data, here a broadly applicable predictive computational model capable of recapitulating both encapsulation strategies is developed. The model is employed to comparatively study the oxygen concentration at different levels of vascularization, transplanted cell density, and spatial distribution, as well as with codelivered adjuvant cells. The model is then validated to be predictive of experimental results of oxygen pressure and local and systemic drug biodistribution in a direct vascularization device with local immunosuppressant delivery. The model highlights that dense vascularization can minimize cell hypoxia while allowing for high cell loading density. In contrast, lower levels of vascularization allow for better drug localization reducing systemic dissemination. Overall, it is shown that this model can serve as a valuable tool for the development and optimization of platform technologies for cell encapsulation.
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Affiliation(s)
- Simone Capuani
- Department of NanomedicineHouston Methodist Research InstituteHoustonTX77030USA
- College of Materials Science and Opto‐Electronic TechnologyUniversity of Chinese Academy of Science (UCAS)Beijing100049China
| | - Jocelyn Nikita Campa‐Carranza
- Department of NanomedicineHouston Methodist Research InstituteHoustonTX77030USA
- School of Medicine and Health SciencesTecnologico de MonterreyMonterreyNL64710Mexico
| | - Nathanael Hernandez
- Department of NanomedicineHouston Methodist Research InstituteHoustonTX77030USA
| | | | - Alessandro Grattoni
- Department of NanomedicineHouston Methodist Research InstituteHoustonTX77030USA
- Department of SurgeryHouston Methodist HospitalHoustonTX77030USA
- Department of Radiation OncologyHouston Methodist HospitalHoustonTX77030USA
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7
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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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8
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Grubelnik V, Zmazek J, Gosak M, Marhl M. The role of anaplerotic metabolism of glucose and glutamine in insulin secretion: A model approach. Biophys Chem 2024; 311:107270. [PMID: 38833963 DOI: 10.1016/j.bpc.2024.107270] [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: 01/31/2024] [Revised: 05/22/2024] [Accepted: 05/22/2024] [Indexed: 06/06/2024]
Abstract
We propose a detailed computational beta cell model that emphasizes the role of anaplerotic metabolism under glucose and glucose-glutamine stimulation. This model goes beyond the traditional focus on mitochondrial oxidative phosphorylation and ATP-sensitive K+ channels, highlighting the predominant generation of ATP from phosphoenolpyruvate in the vicinity of KATP channels. It also underlines the modulatory role of H2O2 as a signaling molecule in the first phase of glucose-stimulated insulin secretion. In the second phase, the model emphasizes the critical role of anaplerotic pathways, activated by glucose stimulation via pyruvate carboxylase and by glutamine via glutamate dehydrogenase. It particularly focuses on the production of NADPH and glutamate as key enhancers of insulin secretion. The predictions of the model are consistent with empirical data, highlighting the complex interplay of metabolic pathways and emphasizing the primary role of glucose and the facilitating role of glutamine in insulin secretion. By delineating these crucial metabolic pathways, the model provides valuable insights into potential therapeutic targets for diabetes.
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Affiliation(s)
- Vladimir Grubelnik
- Faculty of Electrical Engineering and Computer Science, University of Maribor, Koroška cesta 46, 2000 Maribor, Slovenia
| | - Jan Zmazek
- Faculty of Natural Sciences and Mathematics, University of Maribor, Koroška cesta 160, 2000 Maribor, Slovenia
| | - Marko Gosak
- Faculty of Natural Sciences and Mathematics, University of Maribor, Koroška cesta 160, 2000 Maribor, Slovenia; Faculty of Medicine, University of Maribor, Taborska ulica 8, 2000 Maribor, Slovenia; Alma Mater Europaea ECM, Slovenska ulica 17, 2000 Maribor, Slovenia
| | - Marko Marhl
- Faculty of Natural Sciences and Mathematics, University of Maribor, Koroška cesta 160, 2000 Maribor, Slovenia; Faculty of Medicine, University of Maribor, Taborska ulica 8, 2000 Maribor, Slovenia; Faculty of Education, University of Maribor, Koroška cesta 160, 2000 Maribor, Slovenia.
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9
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Patel S, Remedi MS. Loss of β-cell identity and dedifferentiation, not an irreversible process? Front Endocrinol (Lausanne) 2024; 15:1414447. [PMID: 38915897 PMCID: PMC11194313 DOI: 10.3389/fendo.2024.1414447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Accepted: 05/27/2024] [Indexed: 06/26/2024] Open
Abstract
Type 2 diabetes (T2D) is a polygenic metabolic disorder characterized by insulin resistance in peripheral tissues and impaired insulin secretion by the pancreas. While the decline in insulin production and secretion was previously attributed to apoptosis of insulin-producing β-cells, recent studies indicate that β-cell apoptosis rates are relatively low in diabetes. Instead, β-cells primarily undergo dedifferentiation, a process where they lose their specialized identity and transition into non-functional endocrine progenitor-like cells, ultimately leading to β-cell failure. The underlying mechanisms driving β-cell dedifferentiation remain elusive due to the intricate interplay of genetic factors and cellular stress. Understanding these mechanisms holds the potential to inform innovative therapeutic approaches aimed at reversing β-cell dedifferentiation in T2D. This review explores the proposed drivers of β-cell dedifferentiation leading to β-cell failure, and discusses current interventions capable of reversing this process, thus restoring β-cell identity and function.
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Affiliation(s)
- Sumit Patel
- Department of Medicine, Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, South Euclid Avenue, St. Louis, MO, United States
| | - Maria S. Remedi
- Department of Medicine, Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, South Euclid Avenue, St. Louis, MO, United States
- Deparment of Cell Biology and Physiology, Washington University School of Medicine, South Euclid Avenue, St. Louis, MO, United States
- Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, South Euclid Avenue, St. Louis, MO, United States
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10
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Webster KL, Mirmira RG. Beta cell dedifferentiation in type 1 diabetes: sacrificing function for survival? Front Endocrinol (Lausanne) 2024; 15:1427723. [PMID: 38904049 PMCID: PMC11187278 DOI: 10.3389/fendo.2024.1427723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2024] [Accepted: 05/27/2024] [Indexed: 06/22/2024] Open
Abstract
The pathogeneses of type 1 and type 2 diabetes involve the progressive loss of functional beta cell mass, primarily attributed to cellular demise and/or dedifferentiation. While the scientific community has devoted significant attention to unraveling beta cell dedifferentiation in type 2 diabetes, its significance in type 1 diabetes remains relatively unexplored. This perspective article critically analyzes the existing evidence for beta cell dedifferentiation in type 1 diabetes, emphasizing its potential to reduce beta cell autoimmunity. Drawing from recent advancements in both human studies and animal models, we present beta cell identity as a promising target for managing type 1 diabetes. We posit that a better understanding of the mechanisms of beta cell dedifferentiation in type 1 diabetes is key to pioneering interventions that balance beta cell function and immunogenicity.
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Affiliation(s)
| | - Raghavendra G. Mirmira
- Kovler Diabetes Center and the Department of Medicine, The University of Chicago, Chicago, IL, United States
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11
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Muñoz F, Fex M, Moritz T, Mulder H, Cataldo LR. Unique features of β-cell metabolism are lost in type 2 diabetes. Acta Physiol (Oxf) 2024; 240:e14148. [PMID: 38656044 DOI: 10.1111/apha.14148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 02/28/2024] [Accepted: 04/05/2024] [Indexed: 04/26/2024]
Abstract
Pancreatic β cells play an essential role in the control of systemic glucose homeostasis as they sense blood glucose levels and respond by secreting insulin. Upon stimulating glucose uptake in insulin-sensitive tissues post-prandially, this anabolic hormone restores blood glucose levels to pre-prandial levels. Maintaining physiological glucose levels thus relies on proper β-cell function. To fulfill this highly specialized nutrient sensor role, β cells have evolved a unique genetic program that shapes its distinct cellular metabolism. In this review, the unique genetic and metabolic features of β cells will be outlined, including their alterations in type 2 diabetes (T2D). β cells selectively express a set of genes in a cell type-specific manner; for instance, the glucose activating hexokinase IV enzyme or Glucokinase (GCK), whereas other genes are selectively "disallowed", including lactate dehydrogenase A (LDHA) and monocarboxylate transporter 1 (MCT1). This selective gene program equips β cells with a unique metabolic apparatus to ensure that nutrient metabolism is coupled to appropriate insulin secretion, thereby avoiding hyperglycemia, as well as life-threatening hypoglycemia. Unlike most cell types, β cells exhibit specialized bioenergetic features, including supply-driven rather than demand-driven metabolism and a high basal mitochondrial proton leak respiration. The understanding of these unique genetically programmed metabolic features and their alterations that lead to β-cell dysfunction is crucial for a comprehensive understanding of T2D pathophysiology and the development of innovative therapeutic approaches for T2D patients.
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Affiliation(s)
- Felipe Muñoz
- Clinical Research Center, Department of Clinical Sciences in Malmö, Lund University Diabetes Centre, Lund, Sweden
| | - Malin Fex
- Clinical Research Center, Department of Clinical Sciences in Malmö, Lund University Diabetes Centre, Lund, Sweden
| | - Thomas Moritz
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Hindrik Mulder
- Clinical Research Center, Department of Clinical Sciences in Malmö, Lund University Diabetes Centre, Lund, Sweden
| | - Luis Rodrigo Cataldo
- Clinical Research Center, Department of Clinical Sciences in Malmö, Lund University Diabetes Centre, Lund, Sweden
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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12
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Satin LS, Corradi J, Sherman AS. Do We Need a New Hypothesis for KATP Closure in β-Cells? Distinguishing the Baby From the Bathwater. Diabetes 2024; 73:844-848. [PMID: 38640066 PMCID: PMC11109778 DOI: 10.2337/db24-0131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Accepted: 03/15/2024] [Indexed: 04/21/2024]
Affiliation(s)
- Leslie Sherwin Satin
- Department of Pharmacology and Division of Metabolism, Endocrinology and Diabetes, Department of Internal Medicine, Brehm Diabetes Center and Caswell Diabetes Institute, University of Michigan Medical School, Ann Arbor, MI
| | - Jeremías Corradi
- Department of Pharmacology and Division of Metabolism, Endocrinology and Diabetes, Department of Internal Medicine, Brehm Diabetes Center and Caswell Diabetes Institute, University of Michigan Medical School, Ann Arbor, MI
| | - Arthur Stewart Sherman
- Laboratory of Biological Modeling, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD
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van Niekerk DD, van Wyk M, Kouril T, Snoep JL. Kinetic modelling of glycolytic oscillations. Essays Biochem 2024; 68:15-25. [PMID: 38206647 DOI: 10.1042/ebc20230037] [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: 11/06/2023] [Revised: 12/18/2023] [Accepted: 12/19/2023] [Indexed: 01/12/2024]
Abstract
Glycolytic oscillations have been studied for well over 60 years, but aspects of their function, and mechanisms of regulation and synchronisation remain unclear. Glycolysis is amenable to mechanistic mathematical modelling, as its components have been well characterised, and the system can be studied at many organisational levels: in vitro reconstituted enzymes, cell free extracts, individual cells, and cell populations. In recent years, the emergence of individual cell analysis has opened new ways of studying this intriguing system.
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Affiliation(s)
- David D van Niekerk
- Department of Biochemistry, Stellenbosch University, Matieland, South Africa
| | - Morne van Wyk
- Department of Biochemistry, Stellenbosch University, Matieland, South Africa
| | - Theresa Kouril
- Department of Biochemistry, Stellenbosch University, Matieland, South Africa
| | - Jacky L Snoep
- Department of Biochemistry, Stellenbosch University, Matieland, South Africa
- Molecular Cell Biology, Vrije Universiteit, Amsterdam, The Netherlands
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14
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Cuozzo F, Viloria K, Shilleh AH, Nasteska D, Frazer-Morris C, Tong J, Jiao Z, Boufersaoui A, Marzullo B, Rosoff DB, Smith HR, Bonner C, Kerr-Conte J, Pattou F, Nano R, Piemonti L, Johnson PRV, Spiers R, Roberts J, Lavery GG, Clark A, Ceresa CDL, Ray DW, Hodson L, Davies AP, Rutter GA, Oshima M, Scharfmann R, Merrins MJ, Akerman I, Tennant DA, Ludwig C, Hodson DJ. LDHB contributes to the regulation of lactate levels and basal insulin secretion in human pancreatic β cells. Cell Rep 2024; 43:114047. [PMID: 38607916 PMCID: PMC11164428 DOI: 10.1016/j.celrep.2024.114047] [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: 03/16/2023] [Revised: 02/19/2024] [Accepted: 03/19/2024] [Indexed: 04/14/2024] Open
Abstract
Using 13C6 glucose labeling coupled to gas chromatography-mass spectrometry and 2D 1H-13C heteronuclear single quantum coherence NMR spectroscopy, we have obtained a comparative high-resolution map of glucose fate underpinning β cell function. In both mouse and human islets, the contribution of glucose to the tricarboxylic acid (TCA) cycle is similar. Pyruvate fueling of the TCA cycle is primarily mediated by the activity of pyruvate dehydrogenase, with lower flux through pyruvate carboxylase. While the conversion of pyruvate to lactate by lactate dehydrogenase (LDH) can be detected in islets of both species, lactate accumulation is 6-fold higher in human islets. Human islets express LDH, with low-moderate LDHA expression and β cell-specific LDHB expression. LDHB inhibition amplifies LDHA-dependent lactate generation in mouse and human β cells and increases basal insulin release. Lastly, cis-instrument Mendelian randomization shows that low LDHB expression levels correlate with elevated fasting insulin in humans. Thus, LDHB limits lactate generation in β cells to maintain appropriate insulin release.
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Affiliation(s)
- Federica Cuozzo
- Institute of Metabolism and Systems Research (IMSR) and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, Birmingham, UK
| | - Katrina Viloria
- Institute of Metabolism and Systems Research (IMSR) and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, Birmingham, UK; Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM), NIHR Oxford Biomedical Research Centre, Churchill Hospital, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Ali H Shilleh
- Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM), NIHR Oxford Biomedical Research Centre, Churchill Hospital, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Daniela Nasteska
- Institute of Metabolism and Systems Research (IMSR) and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, Birmingham, UK; Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM), NIHR Oxford Biomedical Research Centre, Churchill Hospital, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Charlotte Frazer-Morris
- Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM), NIHR Oxford Biomedical Research Centre, Churchill Hospital, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Jason Tong
- Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM), NIHR Oxford Biomedical Research Centre, Churchill Hospital, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Zicong Jiao
- Institute of Metabolism and Systems Research (IMSR) and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, Birmingham, UK; Geneplus-Beijing, Changping District, Beijing 102206, China
| | - Adam Boufersaoui
- Institute of Metabolism and Systems Research (IMSR) and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, Birmingham, UK
| | - Bryan Marzullo
- Institute of Metabolism and Systems Research (IMSR) and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, Birmingham, UK
| | - Daniel B Rosoff
- Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM), NIHR Oxford Biomedical Research Centre, Churchill Hospital, Radcliffe Department of Medicine, University of Oxford, Oxford, UK; Oxford Kavli Centre for Nanoscience Discovery, University of Oxford, Oxford, UK
| | - Hannah R Smith
- Institute of Metabolism and Systems Research (IMSR) and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, Birmingham, UK
| | - Caroline Bonner
- University of Lille, Institut National de la Santé et de la Recherche Médicale (INSERM), Centre Hospitalier Universitaire de Lille (CHU Lille), Institute Pasteur Lille, U1190 -European Genomic Institute for Diabetes (EGID), F59000 Lille, France
| | - Julie Kerr-Conte
- University of Lille, Institut National de la Santé et de la Recherche Médicale (INSERM), Centre Hospitalier Universitaire de Lille (CHU Lille), Institute Pasteur Lille, U1190 -European Genomic Institute for Diabetes (EGID), F59000 Lille, France
| | - Francois Pattou
- University of Lille, Institut National de la Santé et de la Recherche Médicale (INSERM), Centre Hospitalier Universitaire de Lille (CHU Lille), Institute Pasteur Lille, U1190 -European Genomic Institute for Diabetes (EGID), F59000 Lille, France
| | - Rita Nano
- San Raffaele Diabetes Research Institute, IRCCS Ospedale San Raffaele, Milan, Italy; Vita-Salute San Raffaele University, Milan, Italy
| | - Lorenzo Piemonti
- San Raffaele Diabetes Research Institute, IRCCS Ospedale San Raffaele, Milan, Italy; Vita-Salute San Raffaele University, Milan, Italy
| | - Paul R V Johnson
- Nuffield Department of Surgical Sciences, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Rebecca Spiers
- Nuffield Department of Surgical Sciences, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Jennie Roberts
- Institute of Metabolism and Systems Research (IMSR) and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, Birmingham, UK
| | - Gareth G Lavery
- Institute of Metabolism and Systems Research (IMSR) and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, Birmingham, UK; Centre for Systems Health and Integrated Metabolic Research (SHiMR), Department of Biosciences, School of Science and Technology, Nottingham Trent University, Nottingham, UK
| | - Anne Clark
- Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM), NIHR Oxford Biomedical Research Centre, Churchill Hospital, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Carlo D L Ceresa
- Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM), NIHR Oxford Biomedical Research Centre, Churchill Hospital, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - David W Ray
- Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM), NIHR Oxford Biomedical Research Centre, Churchill Hospital, Radcliffe Department of Medicine, University of Oxford, Oxford, UK; Oxford Kavli Centre for Nanoscience Discovery, University of Oxford, Oxford, UK
| | - Leanne Hodson
- Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM), NIHR Oxford Biomedical Research Centre, Churchill Hospital, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Amy P Davies
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Guy A Rutter
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK; CHUM Research Centre and Faculty of Medicine, University of Montreal, Montreal, QC, Canada; Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Masaya Oshima
- Université Paris Cité, Institut Cochin, INSERM U1016, CNRS UMR 8104, 75014 Paris, France
| | - Raphaël Scharfmann
- Université Paris Cité, Institut Cochin, INSERM U1016, CNRS UMR 8104, 75014 Paris, France
| | - 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
| | - Ildem Akerman
- Institute of Metabolism and Systems Research (IMSR) and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, Birmingham, UK
| | - Daniel A Tennant
- Institute of Metabolism and Systems Research (IMSR) and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, Birmingham, UK.
| | - Christian Ludwig
- Institute of Metabolism and Systems Research (IMSR) and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, Birmingham, UK.
| | - David J Hodson
- Institute of Metabolism and Systems Research (IMSR) and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, Birmingham, UK; Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM), NIHR Oxford Biomedical Research Centre, Churchill Hospital, Radcliffe Department of Medicine, University of Oxford, Oxford, UK.
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15
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Oropeza D, Herrera PL. Glucagon-producing α-cell transcriptional identity and reprogramming towards insulin production. Trends Cell Biol 2024; 34:180-197. [PMID: 37626005 DOI: 10.1016/j.tcb.2023.07.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 07/07/2023] [Accepted: 07/11/2023] [Indexed: 08/27/2023]
Abstract
β-Cell replacement by in situ reprogramming of non-β-cells is a promising diabetes therapy. Following the observation that near-total β-cell ablation in adult mice triggers the reprogramming of pancreatic α-, δ-, and γ-cells into insulin (INS)-producing cells, recent studies are delving deep into the mechanisms controlling adult α-cell identity. Systematic analyses of the α-cell transcriptome and epigenome have started to pinpoint features that could be crucial for maintaining α-cell identity. Using different transgenic and chemical approaches, significant advances have been made in reprogramming α-cells in vivo into INS-secreting cells in mice. The recent reprogramming of human α-cells in vitro is an important step forward that must now be complemented with a comprehensive molecular dissection of the mechanisms controlling α-cell identity.
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Affiliation(s)
- Daniel Oropeza
- Department of Genetic Medicine and Development, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Pedro Luis Herrera
- Department of Genetic Medicine and Development, Faculty of Medicine, University of Geneva, Geneva, Switzerland.
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16
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Rivera Nieves AM, Wauford BM, Fu A. Mitochondrial bioenergetics, metabolism, and beyond in pancreatic β-cells and diabetes. Front Mol Biosci 2024; 11:1354199. [PMID: 38404962 PMCID: PMC10884328 DOI: 10.3389/fmolb.2024.1354199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Accepted: 01/17/2024] [Indexed: 02/27/2024] Open
Abstract
In Type 1 and Type 2 diabetes, pancreatic β-cell survival and function are impaired. Additional etiologies of diabetes include dysfunction in insulin-sensing hepatic, muscle, and adipose tissues as well as immune cells. An important determinant of metabolic health across these various tissues is mitochondria function and structure. This review focuses on the role of mitochondria in diabetes pathogenesis, with a specific emphasis on pancreatic β-cells. These dynamic organelles are obligate for β-cell survival, function, replication, insulin production, and control over insulin release. Therefore, it is not surprising that mitochondria are severely defective in diabetic contexts. Mitochondrial dysfunction poses challenges to assess in cause-effect studies, prompting us to assemble and deliberate the evidence for mitochondria dysfunction as a cause or consequence of diabetes. Understanding the precise molecular mechanisms underlying mitochondrial dysfunction in diabetes and identifying therapeutic strategies to restore mitochondrial homeostasis and enhance β-cell function are active and expanding areas of research. In summary, this review examines the multidimensional role of mitochondria in diabetes, focusing on pancreatic β-cells and highlighting the significance of mitochondrial metabolism, bioenergetics, calcium, dynamics, and mitophagy in the pathophysiology of diabetes. We describe the effects of diabetes-related gluco/lipotoxic, oxidative and inflammation stress on β-cell mitochondria, as well as the role played by mitochondria on the pathologic outcomes of these stress paradigms. By examining these aspects, we provide updated insights and highlight areas where further research is required for a deeper molecular understanding of the role of mitochondria in β-cells and diabetes.
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Affiliation(s)
- Alejandra María Rivera Nieves
- Diabetes Center of Excellence, University of Massachusetts Chan Medical School, Worcester, MA, United States
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Brian Michael Wauford
- Diabetes Center of Excellence, University of Massachusetts Chan Medical School, Worcester, MA, United States
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Accalia Fu
- Diabetes Center of Excellence, University of Massachusetts Chan Medical School, Worcester, MA, United States
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, United States
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17
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Rushin A, McLeod MA, Ragavan M, Merritt ME. Observing exocrine pancreas metabolism using a novel pancreas perfusion technique in combination with hyperpolarized [1- 13 C]pyruvate. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2023; 61:748-758. [PMID: 37482899 PMCID: PMC10800648 DOI: 10.1002/mrc.5382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 06/28/2023] [Accepted: 07/06/2023] [Indexed: 07/25/2023]
Abstract
In a clinical setting, ex vivo perfusions are routinely used to maintain and assess organ viability prior to transplants. Organ perfusions are also a model system to examine metabolic flux while retaining the local physiological structure, with significant success using hyperpolarized (HP) 13 C NMR in this context. We use a novel exocrine pancreas perfusion technique via the common bile duct to assess acinar cell metabolism with HP [1-13 C]pyruvate. The exocrine component of the pancreas produces digestive enzymes through the ductal system and is often neglected in research on the pancreas. Real-time production of [1-13 C]lactate, [1-13 C]alanine, [1-13 C]malate, [4-13 C]malate, [1-13 C]aspartate, and H13 CO3 - was detected. The appearance of these resonances indicates flux through both pyruvate dehydrogenase and pyruvate carboxylase. We studied excised pancreata from C57BL/6J mice and NOD.Rag1-/- .AI4α/β mice, a commonly used model of Type 1 Diabetes (T1D). Pancreata from the T1D mice displayed increased lactate to alanine ratio without changes in oxygen consumption, signifying increased cytosolic NADH levels. The mass isotopologue analysis of the extracted pancreas tissue using gas chromatography-mass spectrometry revealed confirmatory 13 C enrichment in multiple TCA cycle metabolites that are products of pyruvate carboxylation. The methodology presented here has the potential to provide insight into mechanisms underlying several pancreatic diseases, such as diabetes, pancreatitis, and pancreatic cancer.
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Affiliation(s)
- Anna Rushin
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Marc A. McLeod
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Mukundan Ragavan
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Matthew E. Merritt
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, Florida, USA
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18
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Perrier J, Nawrot M, Madec AM, Chikh K, Chauvin MA, Damblon C, Sabatier J, Thivolet CH, Rieusset J, Rautureau GJP, Panthu B. Human Pancreatic Islets React to Glucolipotoxicity by Secreting Pyruvate and Citrate. Nutrients 2023; 15:4791. [PMID: 38004183 PMCID: PMC10674605 DOI: 10.3390/nu15224791] [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: 09/27/2023] [Revised: 11/07/2023] [Accepted: 11/10/2023] [Indexed: 11/26/2023] Open
Abstract
Progressive decline in pancreatic beta-cell function is central to the pathogenesis of type 2 diabetes (T2D). Here, we explore the relationship between the beta cell and its nutritional environment, asking how an excess of energy substrate leads to altered energy production and subsequent insulin secretion. Alterations in intracellular metabolic homeostasis are key markers of islets with T2D, but changes in cellular metabolite exchanges with their environment remain unknown. We answered this question using nuclear magnetic resonance-based quantitative metabolomics and evaluated the consumption or secretion of 31 extracellular metabolites from healthy and T2D human islets. Islets were also cultured under high levels of glucose and/or palmitate to induce gluco-, lipo-, and glucolipotoxicity. Biochemical analyses revealed drastic alterations in the pyruvate and citrate pathways, which appear to be associated with mitochondrial oxoglutarate dehydrogenase (OGDH) downregulation. We repeated these manipulations on the rat insulinoma-derived beta-pancreatic cell line (INS-1E). Our results highlight an OGDH downregulation with a clear effect on the pyruvate and citrate pathways. However, citrate is directed to lipogenesis in the INS-1E cells instead of being secreted as in human islets. Our results demonstrate the ability of metabolomic approaches performed on culture media to easily discriminate T2D from healthy and functional islets.
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Affiliation(s)
- Johan Perrier
- Laboratoire CarMeN, UMR INSERM U1060/INRAE U1397, University of Lyon, Université Claude Bernard Lyon 1, 69310 Pierre-Bénite, France
| | - Margaux Nawrot
- Laboratoire CarMeN, UMR INSERM U1060/INRAE U1397, University of Lyon, Université Claude Bernard Lyon 1, 69310 Pierre-Bénite, France
| | - Anne-Marie Madec
- Laboratoire CarMeN, UMR INSERM U1060/INRAE U1397, University of Lyon, Université Claude Bernard Lyon 1, 69310 Pierre-Bénite, France
| | - Karim Chikh
- Laboratoire CarMeN, UMR INSERM U1060/INRAE U1397, University of Lyon, Université Claude Bernard Lyon 1, 69310 Pierre-Bénite, France
- Department of Endocrinology and Diabetes, Hospices Civils de Lyon, Hopital Lyon Sud, 69310 Pierre-Bénite, France
| | - Marie-Agnès Chauvin
- Laboratoire CarMeN, UMR INSERM U1060/INRAE U1397, University of Lyon, Université Claude Bernard Lyon 1, 69310 Pierre-Bénite, France
| | - Christian Damblon
- Unité de Recherche MolSys, Faculté des Sciences, Université de Liège, 99131 Liège, Belgium
| | - Julia Sabatier
- Laboratory of Cell Therapy for Diabetes (LTCD), PRIMS Facility, Institute for Regenerative Medicine and Biotherapy (IRMB), University Hospital of Montpellier, 34295 Montpellier, France
| | - Charles H. Thivolet
- Laboratoire CarMeN, UMR INSERM U1060/INRAE U1397, University of Lyon, Université Claude Bernard Lyon 1, 69310 Pierre-Bénite, France
- Department of Endocrinology and Diabetes, Hospices Civils de Lyon, Hopital Lyon Sud, 69310 Pierre-Bénite, France
| | - Jennifer Rieusset
- Laboratoire CarMeN, UMR INSERM U1060/INRAE U1397, University of Lyon, Université Claude Bernard Lyon 1, 69310 Pierre-Bénite, France
| | - Gilles J. P. Rautureau
- Centre de Résonance Magnétique Nucléaire à Très Hauts Champs, UMR 5082 CNRS, ENS Lyon, UCBL, Université de Lyon, 69100 Villeurbanne, France
| | - Baptiste Panthu
- Laboratoire CarMeN, UMR INSERM U1060/INRAE U1397, University of Lyon, Université Claude Bernard Lyon 1, 69310 Pierre-Bénite, France
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19
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Jasra IT, Cuesta-Gomez N, Verhoeff K, Marfil-Garza BA, Dadheech N, Shapiro AMJ. Mitochondrial regulation in human pluripotent stem cells during reprogramming and β cell differentiation. Front Endocrinol (Lausanne) 2023; 14:1236472. [PMID: 37929027 PMCID: PMC10623316 DOI: 10.3389/fendo.2023.1236472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Accepted: 10/06/2023] [Indexed: 11/07/2023] Open
Abstract
Mitochondria are the powerhouse of the cell and dynamically control fundamental biological processes including cell reprogramming, pluripotency, and lineage specification. Although remarkable progress in induced pluripotent stem cell (iPSC)-derived cell therapies has been made, very little is known about the role of mitochondria and the mechanisms involved in somatic cell reprogramming into iPSC and directed reprogramming of iPSCs in terminally differentiated cells. Reprogramming requires changes in cellular characteristics, genomic and epigenetic regulation, as well as major mitochondrial metabolic changes to sustain iPSC self-renewal, pluripotency, and proliferation. Differentiation of autologous iPSC into terminally differentiated β-like cells requires further metabolic adaptation. Many studies have characterized these alterations in signaling pathways required for the generation and differentiation of iPSC; however, very little is known regarding the metabolic shifts that govern pluripotency transition to tissue-specific lineage differentiation. Understanding such metabolic transitions and how to modulate them is essential for the optimization of differentiation processes to ensure safe iPSC-derived cell therapies. In this review, we summarize the current understanding of mitochondrial metabolism during somatic cell reprogramming to iPSCs and the metabolic shift that occurs during directed differentiation into pancreatic β-like cells.
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Affiliation(s)
- Ila Tewari Jasra
- Clinical Islet Transplant Program, Department of Surgery, Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada
| | - Nerea Cuesta-Gomez
- Clinical Islet Transplant Program, Department of Surgery, Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada
| | - Kevin Verhoeff
- Clinical Islet Transplant Program, Department of Surgery, Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada
| | - Braulio A. Marfil-Garza
- Clinical Islet Transplant Program, Department of Surgery, Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada
- Tecnologico de Monterrey, The Institute for Obesity Research, Monterrey, Nuevo Leon, Mexico
| | - Nidheesh Dadheech
- Clinical Islet Transplant Program, Department of Surgery, Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada
| | - A. M. James Shapiro
- Clinical Islet Transplant Program, Department of Surgery, Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada
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20
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Chen YC, Taylor AJ, Fulcher JM, Swensen AC, Dai XQ, Komba M, Wrightson KL, Fok K, Patterson AE, Klein Geltink RI, MacDonald PE, Qian WJ, Verchere CB. Deletion of Carboxypeptidase E in β-Cells Disrupts Proinsulin Processing but Does Not Lead to Spontaneous Development of Diabetes in Mice. Diabetes 2023; 72:1277-1288. [PMID: 37364047 PMCID: PMC10450824 DOI: 10.2337/db22-0945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Accepted: 06/22/2023] [Indexed: 06/28/2023]
Abstract
Carboxypeptidase E (CPE) facilitates the conversion of prohormones into mature hormones and is highly expressed in multiple neuroendocrine tissues. Carriers of CPE mutations have elevated plasma proinsulin and develop severe obesity and hyperglycemia. We aimed to determine whether loss of Cpe in pancreatic β-cells disrupts proinsulin processing and accelerates development of diabetes and obesity in mice. Pancreatic β-cell-specific Cpe knockout mice (βCpeKO; Cpefl/fl x Ins1Cre/+) lack mature insulin granules and have elevated proinsulin in plasma; however, glucose-and KCl-stimulated insulin secretion in βCpeKO islets remained intact. High-fat diet-fed βCpeKO mice showed weight gain and glucose tolerance comparable with those of Wt littermates. Notably, β-cell area was increased in chow-fed βCpeKO mice and β-cell replication was elevated in βCpeKO islets. Transcriptomic analysis of βCpeKO β-cells revealed elevated glycolysis and Hif1α-target gene expression. On high glucose challenge, β-cells from βCpeKO mice showed reduced mitochondrial membrane potential, increased reactive oxygen species, reduced MafA, and elevated Aldh1a3 transcript levels. Following multiple low-dose streptozotocin injections, βCpeKO mice had accelerated development of hyperglycemia with reduced β-cell insulin and Glut2 expression. These findings suggest that Cpe and proper proinsulin processing are critical in maintaining β-cell function during the development of hyperglycemia. ARTICLE HIGHLIGHTS Carboxypeptidase E (Cpe) is an enzyme that removes the carboxy-terminal arginine and lysine residues from peptide precursors. Mutations in CPE lead to obesity and type 2 diabetes in humans, and whole-body Cpe knockout or mutant mice are obese and hyperglycemic and fail to convert proinsulin to insulin. We show that β-cell-specific Cpe deletion in mice (βCpeKO) does not lead to the development of obesity or hyperglycemia, even after prolonged high-fat diet treatment. However, β-cell proliferation rate and β-cell area are increased, and the development of hyperglycemia induced by multiple low-dose streptozotocin injections is accelerated in βCpeKO mice.
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Affiliation(s)
- Yi-Chun Chen
- Department of Surgery, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
- BC Children’s Hospital Research Institute, Vancouver, British Columbia, Canada
| | - Austin J. Taylor
- BC Children’s Hospital Research Institute, Vancouver, British Columbia, Canada
- Department of Pathology and Laboratory Medicine, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - James M. Fulcher
- Integrative Omics, Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA
| | - Adam C. Swensen
- Integrative Omics, Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA
| | - Xiao-Qing Dai
- Department of Pharmacology, University of Alberta, Edmonton, Alberta, Canada
| | - Mitsuhiro Komba
- Department of Surgery, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
- BC Children’s Hospital Research Institute, Vancouver, British Columbia, Canada
| | | | - Kenny Fok
- BC Children’s Hospital Research Institute, Vancouver, British Columbia, Canada
| | - Annette E. Patterson
- BC Children’s Hospital Research Institute, Vancouver, British Columbia, Canada
- Department of Pathology and Laboratory Medicine, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Ramon I. Klein Geltink
- BC Children’s Hospital Research Institute, Vancouver, British Columbia, Canada
- Department of Pathology and Laboratory Medicine, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | | | - Wei-Jun Qian
- Integrative Omics, Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA
| | - C. Bruce Verchere
- Department of Surgery, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
- BC Children’s Hospital Research Institute, Vancouver, British Columbia, Canada
- Department of Pathology and Laboratory Medicine, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
- Centre for Molecular Medicine and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
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21
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Yago H, Homma J, Sekine H, Higashi Y, Sakurai H, Shimizu T. The bioengineering of perfusable endocrine tissue with anastomosable blood vessels. Biofabrication 2023; 15:045010. [PMID: 37487489 DOI: 10.1088/1758-5090/ace9fc] [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: 01/25/2023] [Accepted: 07/24/2023] [Indexed: 07/26/2023]
Abstract
Organ transplantation is a definitive treatment for endocrine disorders, but donor shortages limit the use of this technique. The development of regenerative therapies would revolutionize the treatment of endocrine disorders. As is the case for harvested organs, the ideal bioengineered graft would comprise vascularized endocrine tissue, contain blood vessels that could be anastomosed to host vessels, have stable blood flow, and be suitable for transplantation into various sites. Here, we describe a transplantable endocrine tissue graft that was fabricated byex vivoperfusion of tricultured cell sheets (isletβ-cells, vascular endothelial cells (vECs), and mesenchymal stem cells (MSCs)) on a vascularized tissue flap ofin vivoorigin. The present study has three key findings. First, mild hypothermic conditions enhanced the success ofex vivoperfusion culture. Specifically, graft construction failed at 37 °C but succeeded at 32 °C (mild hypothermia), and endocrine tissue fabricated under mild hypothermia contained aggregations of isletβ-cells surrounded by dense vascular networks. Second, the construction of transplantable endocrine tissue byex vivoperfusion culture was better achieved using a vascular flap (VF) than a muscle flap. Third, the endocrine tissue construct generated using a VF could be transplanted into the rat by anastomosis of the graft artery and vein to host blood vessels, and the graft secreted insulin into the host's circulatory system for at least two weeks after transplantation. Endocrine tissues bioengineered using these techniques potentially could be used as novel endocrine therapies.
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Affiliation(s)
- Hiroki Yago
- Institute of Advanced Biomedical Engineering and Science, Tokyo Women's Medical University, Tokyo, Japan
- Department of Plastic and Reconstructive Surgery, Tokyo Women's Medical University, Tokyo, Japan
| | - Jun Homma
- Institute of Advanced Biomedical Engineering and Science, Tokyo Women's Medical University, Tokyo, Japan
| | - Hidekazu Sekine
- Institute of Advanced Biomedical Engineering and Science, Tokyo Women's Medical University, Tokyo, Japan
| | - Yuhei Higashi
- Institute of Advanced Biomedical Engineering and Science, Tokyo Women's Medical University, Tokyo, Japan
- Tokaihit Co., Ltd, Shizuoka, Japan
| | - Hiroyuki Sakurai
- Department of Plastic and Reconstructive Surgery, Tokyo Women's Medical University, Tokyo, Japan
| | - Tatsuya Shimizu
- Institute of Advanced Biomedical Engineering and Science, Tokyo Women's Medical University, Tokyo, Japan
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22
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Son J, Accili D. Reversing pancreatic β-cell dedifferentiation in the treatment of type 2 diabetes. Exp Mol Med 2023; 55:1652-1658. [PMID: 37524865 PMCID: PMC10474037 DOI: 10.1038/s12276-023-01043-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 03/29/2023] [Accepted: 04/24/2023] [Indexed: 08/02/2023] Open
Abstract
The maintenance of glucose homeostasis is fundamental for survival and health. Diabetes develops when glucose homeostasis fails. Type 2 diabetes (T2D) is characterized by insulin resistance and pancreatic β-cell failure. The failure of β-cells to compensate for insulin resistance results in hyperglycemia, which in turn drives altered lipid metabolism and β-cell failure. Thus, insulin secretion by pancreatic β-cells is a primary component of glucose homeostasis. Impaired β-cell function and reduced β-cell mass are found in diabetes. Both features stem from a failure to maintain β-cell identity, which causes β-cells to dedifferentiate into nonfunctional endocrine progenitor-like cells or to trans-differentiate into other endocrine cell types. In this regard, one of the key issues in achieving disease modification is how to reestablish β-cell identity. In this review, we focus on the causes and implications of β-cell failure, as well as its potential reversibility as a T2D treatment.
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Affiliation(s)
- Jinsook Son
- Department of Medicine and Naomi Berrie Diabetes Center, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, 10032, USA.
| | - Domenico Accili
- Department of Medicine and Naomi Berrie Diabetes Center, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, 10032, USA
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23
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Ashcroft FM. KATP Channels and the Metabolic Regulation of Insulin Secretion in Health and Disease: The 2022 Banting Medal for Scientific Achievement Award Lecture. Diabetes 2023; 72:693-702. [PMID: 37815796 PMCID: PMC10202764 DOI: 10.2337/dbi22-0030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 02/28/2023] [Indexed: 10/11/2023]
Abstract
Diabetes is characterized by elevation of plasma glucose due to an insufficiency of the hormone insulin and is associated with both inadequate insulin secretion and impaired insulin action. The Banting Medal for Scientific Achievement Commemorates the work of Sir Frederick Banting, a member of the team that first used insulin to treat a patient with diabetes almost exactly one hundred years ago on 11 January 1922. This article is based on my Banting lecture of 2022 and concerns the mechanism of glucose-stimulated insulin secretion from pancreatic β-cells, with an emphasis on the metabolic regulation of the KATP channel. This channel plays a central role in insulin release. Its closure in response to metabolically generated changes in the intracellular concentrations of ATP and MgADP stimulates β-cell electrical activity and insulin granule exocytosis. Activating mutations in KATP channel genes that impair the ability of the channel to respond to ATP give rise to neonatal diabetes. Impaired KATP channel regulation may also play a role in type 2 diabetes. I conjecture that KATP channel closure in response to glucose is reduced because of impaired glucose metabolism, which fails to generate a sufficient increase in ATP. Consequently, glucose-stimulated β-cell electrical activity is less. As ATP is also required for insulin granule exocytosis, both reduced exocytosis and less β-cell electrical activity may contribute to the reduction in insulin secretion. I emphasize that what follows is not a definitive review of the topic but a personal account of the contribution of my team to the field that is based on my Banting lecture.
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Affiliation(s)
- Frances M. Ashcroft
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, U.K
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24
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Tamarit-Rodriguez J. Metabolic Role of GABA in the Secretory Function of Pancreatic β-Cells: Its Hypothetical Implication in β-Cell Degradation in Type 2 Diabetes. Metabolites 2023; 13:697. [PMID: 37367856 DOI: 10.3390/metabo13060697] [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: 04/22/2023] [Revised: 05/22/2023] [Accepted: 05/24/2023] [Indexed: 06/28/2023] Open
Abstract
The stimulus-secretion coupling of a glucose-induced release is generally attributed to the metabolism of the hexose in the β-cells in the glycolytic pathway and the citric acid cycle. Glucose metabolism generates an increased cytosolic concentration of ATP and of the ATP/ADP ratio that closes the ATP-dependent K+-channel at the plasma membrane. The resultant depolarization of the β-cells opens voltage-dependent Ca2+-channels at the plasma membrane that triggers the exocytosis of insulin secretory granules. The secretory response is biphasic with a first and transient peak followed by a sustained phase. The first phase is reproduced by a depolarization of the β-cells with high extracellular KCl maintaining the KATP-channels open with diazoxide (triggering phase); the sustained phase (amplifying phase) depends on the participation of metabolic signals that remain to be determined. Our group has been investigating for several years the participation of the β-cell GABA metabolism in the stimulation of insulin secretion by three different secretagogues (glucose, a mixture of L-leucine plus L-glutamine, and some branched chain alpha-ketoacids, BCKAs). They stimulate a biphasic secretion of insulin accompanied by a strong suppression of the intracellular islet content of gamma-aminobutyric acid (GABA). As the islet GABA release simultaneously decreased, it was concluded that this resulted from an increased GABA shunt metabolism. The entrance of GABA into the shunt is catalyzed by GABA transaminase (GABAT) that transfers an amino group between GABA and alpha-ketoglutarate, resulting in succinic acid semialdehyde (SSA) and L-glutamate. SSA is oxidized to succinic acid that is further oxidized in the citric acid cycle. Inhibitors of GABAT (gamma-vinyl GABA, gabaculine) or glutamic acid decarboxylating activity (GAD), allylglycine, partially suppress the secretory response as well as GABA metabolism and islet ATP content and the ATP/ADP ratio. It is concluded that the GABA shunt metabolism contributes together with the own metabolism of metabolic secretagogues to increase islet mitochondrial oxidative phosphorylation. These experimental findings emphasize that the GABA shunt metabolism is a previously unrecognized anaplerotic mitochondrial pathway feeding the citric acid cycle with a β-cell endogenous substrate. It is therefore a postulated alternative to the proposed mitochondrial cataplerotic pathway(s) responsible for the amplification phase of insulin secretion. It is concluded the new postulated alternative suggests a possible new mechanism of β-cell degradation in type 2 (perhaps also in type 1) diabetes.
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25
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Jiang H, Jiang FX. Human pluripotent stem cell-derived β cells: Truly immature islet β cells for type 1 diabetes therapy? World J Stem Cells 2023; 15:182-195. [PMID: 37180999 PMCID: PMC10173812 DOI: 10.4252/wjsc.v15.i4.182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 01/30/2023] [Accepted: 03/20/2023] [Indexed: 04/26/2023] Open
Abstract
A century has passed since the Nobel Prize winning discovery of insulin, which still remains the mainstay treatment for type 1 diabetes mellitus (T1DM) to this day. True to the words of its discoverer Sir Frederick Banting, “insulin is not a cure for diabetes, it is a treatment”, millions of people with T1DM are dependent on daily insulin medications for life. Clinical donor islet transplantation has proven that T1DM is curable, however due to profound shortages of donor islets, it is not a mainstream treatment option for T1DM. Human pluripotent stem cell derived insulin-secreting cells, pervasively known as stem cell-derived β cells (SC-β cells), are a promising alternative source and have the potential to become a T1DM treatment through cell replacement therapy. Here we briefly review how islet β cells develop and mature in vivo and several types of reported SC-β cells produced using different ex vivo protocols in the last decade. Although some markers of maturation were expressed and glucose stimulated insulin secretion was shown, the SC-β cells have not been directly compared to their in vivo counterparts, generally have limited glucose response, and are not yet fully matured. Due to the presence of extra-pancreatic insulin-expressing cells, and ethical and technological issues, further clarification of the true nature of these SC-β cells is required.
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Affiliation(s)
- Helen Jiang
- Sir Charles Gairdner Hospital, University of Western Australia, Perth 6009, Australia
| | - Fang-Xu Jiang
- School of Biomedical Sciences, University of Western Australia, Perth 6009, Australia
- School of Health and Medical Sciences, Edith Cowan University, Perth 6027, Australia
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26
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Turbitt J, Brennan L, Moffett RC, Flatt PR, Johnson PRV, Tarasov AI, McClenaghan NH. NKCC transport mediates the insulinotropic effects of taurine and other small neutral amino acids. Life Sci 2023; 316:121402. [PMID: 36669678 DOI: 10.1016/j.lfs.2023.121402] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Revised: 01/04/2023] [Accepted: 01/13/2023] [Indexed: 01/19/2023]
Abstract
AIMS Despite its high concentration in pancreatic islets of Langerhans and broad range of antihyperglycemic effects, the route facilitating the import of dietary taurine into pancreatic β-cell and mechanisms underlying its insulinotropic activity are unclear. We therefore studied the impact of taurine on beta-cell function, alongside that of other small neutral amino acids, L-alanine and L-proline. MAIN METHODS Pharmacological profiling of insulin secretion was conducted using clonal BRIN BD11 β-cells, the impact of taurine on the metabolic fate of glucose carbons was assessed using NMR and the findings were verified by real-time imaging of Ca2+ dynamics in the cytosol of primary mouse and human islet beta-cells. KEY FINDINGS In our hands, taurine, alanine and proline induced secretory responses that were dependent on the plasma membrane depolarisation, import of Ca2+, homeostasis of K+ and Na+ as well as on cell glycolytic and oxidative metabolism. Taurine shifted the balance between the oxidation and anaplerosis towards the latter, in BRIN BD11 beta-cells. Furthermore, the amino acid signalling was significantly attenuated by inhibition of Na+-K+-Cl- symporter (NKCC). SIGNIFICANCE These data suggest that taurine, like L-alanine and L-proline, acutely induces glucose-dependent insulin-secretory responses by modulating electrogenic Na+ transport, with potential role of intracellular K+ and Cl- in the signal transduction. The acute action delineated would be consistent with antidiabetic potential of dietary taurine supplementation.
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Affiliation(s)
- Julie Turbitt
- School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine BT52 1SA, UK
| | - Lorraine Brennan
- UCD Institute of Food and Health, UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Ireland; UCD Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland.
| | - R Charlotte Moffett
- School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine BT52 1SA, UK.
| | - Peter R Flatt
- School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine BT52 1SA, UK.
| | - Paul R V Johnson
- Nuffeld Department of Surgical Sciences, Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Headington, OX3 7LE Oxford, UK; Oxford Biomedical Research Centre (OxBRC), UK.
| | - Andrei I Tarasov
- School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine BT52 1SA, UK; Nuffeld Department of Surgical Sciences, Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Headington, OX3 7LE Oxford, UK; Oxford Biomedical Research Centre (OxBRC), UK.
| | - Neville H McClenaghan
- School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine BT52 1SA, UK; Department of Life Sciences, Atlantic Technological University, Ash Lane, Sligo, F91 YW50, Ireland.
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27
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Yeo CT, Kropp EM, Hansen PA, Pereckas M, Oleson BJ, Naatz A, Stancill JS, Ross KA, Gundry RL, Corbett JA. β-cell-selective inhibition of DNA damage response signaling by nitric oxide is associated with an attenuation in glucose uptake. J Biol Chem 2023; 299:102994. [PMID: 36773802 PMCID: PMC10023961 DOI: 10.1016/j.jbc.2023.102994] [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: 09/12/2022] [Revised: 01/31/2023] [Accepted: 02/01/2023] [Indexed: 02/11/2023] Open
Abstract
Nitric oxide (NO) plays a dual role in regulating DNA damage response (DDR) signaling in pancreatic β-cells. As a genotoxic agent, NO activates two types of DDR signaling; however, when produced at micromolar levels by the inducible isoform of NO synthase, NO inhibits DDR signaling and DDR-induced apoptosis in a β-cell-selective manner. DDR signaling inhibition by NO correlates with mitochondrial oxidative metabolism inhibition and decreases in ATP and NAD+. Unlike most cell types, β-cells do not compensate for impaired mitochondrial oxidation by increasing glycolytic flux, and this metabolic inflexibility leads to a decrease in ATP and NAD+. Here, we used multiple analytical approaches to determine changes in intermediary metabolites in β-cells and non-β-cells treated with NO or complex I inhibitor rotenone. In addition to ATP and NAD+, glycolytic and tricarboxylic acid cycle intermediates as well as NADPH are significantly decreased in β-cells treated with NO or rotenone. Consistent with glucose-6-phosphate residing at the metabolic branchpoint for glycolysis and the pentose phosphate pathway (NADPH), we show that mitochondrial oxidation inhibitors limit glucose uptake in a β-cell-selective manner. Our findings indicate that the β-cell-selective inhibition of DDR signaling by NO is associated with a decrease in ATP to levels that fall significantly below the KM for ATP of glucokinase (glucose uptake) and suggest that this action places the β-cell in a state of suspended animation where it is metabolically inert until NO is removed, and metabolic function can be restored.
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Affiliation(s)
- Chay Teng Yeo
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Erin M Kropp
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Polly A Hansen
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Michael Pereckas
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Bryndon J Oleson
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Aaron Naatz
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Jennifer S Stancill
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Kyle A Ross
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Rebekah L Gundry
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - John A Corbett
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.
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28
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Halliez C, Ibrahim H, Otonkoski T, Mallone R. In vitro beta-cell killing models using immune cells and human pluripotent stem cell-derived islets: Challenges and opportunities. Front Endocrinol (Lausanne) 2023; 13:1076683. [PMID: 36726462 PMCID: PMC9885197 DOI: 10.3389/fendo.2022.1076683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 12/23/2022] [Indexed: 01/19/2023] Open
Abstract
Type 1 diabetes (T1D) is a disease of both autoimmunity and β-cells. The β-cells play an active role in their own demise by mounting defense mechanisms that are insufficient at best, and that can become even deleterious in the long term. This complex crosstalk is important to understanding the physiological defense mechanisms at play in healthy conditions, their alterations in the T1D setting, and therapeutic agents that may boost such mechanisms. Robust protocols to develop stem-cell-derived islets (SC-islets) from human pluripotent stem cells (hPSCs), and islet-reactive cytotoxic CD8+ T-cells from peripheral blood mononuclear cells offer unprecedented opportunities to study this crosstalk. Challenges to develop in vitro β-cell killing models include the cluster morphology of SC-islets, the relatively weak cytotoxicity of most autoimmune T-cells and the variable behavior of in vitro expanded CD8+ T-cells. These challenges may however be highly rewarding in light of the opportunities offered by such models. Herein, we discuss these opportunities including: the β-cell/immune crosstalk in an islet microenvironment; the features that make β-cells more sensitive to autoimmunity; therapeutic agents that may modulate β-cell vulnerability; and the possibility to perform analyses in an autologous setting, i.e., by generating T-cell effectors and SC-islets from the same donor.
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Affiliation(s)
- Clémentine Halliez
- Université Paris Cité, Institut Cochin, CNRS, INSERM, Paris, France
- Assistance Publique Hôpitaux de Paris, Service de Diabétologie et Immunologie Clinique, Cochin Hospital, Paris, France
| | - Hazem Ibrahim
- Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Timo Otonkoski
- Assistance Publique Hôpitaux de Paris, Service de Diabétologie et Immunologie Clinique, Cochin Hospital, Paris, France
- Department of Pediatrics, Helsinki University Hospital, Helsinki, Finland
| | - Roberto Mallone
- Université Paris Cité, Institut Cochin, CNRS, INSERM, Paris, France
- Assistance Publique Hôpitaux de Paris, Service de Diabétologie et Immunologie Clinique, Cochin Hospital, Paris, France
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29
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Khomari F, Kiani B, Alizadeh-Fanalou S, Babaei M, Kalantari-Hesari A, Alipourfard I, Mirzaei F, Yarahmadi S, Bahreini E. Effectiveness of Hydroalcoholic Seed Extract of Securigera securidaca on Pancreatic Local Renin-Angiotensin System and Its Alternative Pathway in Streptozotocin-Induced Diabetic Animal Model. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2023; 2023:7285036. [PMID: 36647426 PMCID: PMC9840543 DOI: 10.1155/2023/7285036] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Revised: 12/17/2022] [Accepted: 12/22/2022] [Indexed: 01/09/2023]
Abstract
Background Available data suggest inhibition of the pancreatic local-renin-angiotensin system (RAS) reduces tissue complications of diabetes. The purpose of the present study was to investigate the effect of hydroalcoholic seed extract of Securigera securidaca (S. securidaca) (HESS) on the pancreatic local-RAS and its alternative pathway. Methods Three doses of HESS were orally administered to three groups of diabetic male Wistar rats, and the results were compared with both diabetic and healthy control groups. After 35 days of treatment, the groups were assessed for the levels of pancreatic local-RAS components, including renin, angiotensinogen, ACE, and Ang II, as well as ACE2 and Ang-(1-7) in the alternative pathway. The effect of herbal medicine treatment on tissue damage status was investigated by evaluating tissue levels of oxidative stress, proinflammatory and anti-inflammatory cytokines, and through histopathological examination of the pancreas. Results HESS showed a dose-dependent palliative effect on the tissue oxidative stress profile (P < 0.05) as well as the levels of pancreatic local-RAS components (P < 0.05), compared to diabetic control group. Considering the interrelationship between tissue oxidative stress and local-RAS activity, the moderating effect of HESS on this relationship could be attributed to the increase in total tissue antioxidant capacity (TAC) and pancreatic Ang-(1-7) concentration. Decrease in local-RAS activity was associated with decrease in the tissue levels of inflammatory cytokines (IL1, IL6, and TNFα) (P < 0.05) and increase in the levels of anti-inflammatory cytokine of IL-10 (P < 0.05). In addition, histological results were consistent with tissue biochemical results. Conclusions Due to the reduction of local pancreatic RAS activity as well as oxidative stress and proinflammatory cytokines following treatment with HESS, S. securidaca seed can be proposed as a suitable herbal supplement in the drug-treatment of diabetes.
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Affiliation(s)
- Fatemeh Khomari
- Department of Biochemistry, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Bahar Kiani
- Department of Biochemistry, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Shahin Alizadeh-Fanalou
- Nephrology and Kidney Transplant center, Clinical Research Institute, Urmia University of Medical Sciences, Urmia, Iran
| | - Mohammad Babaei
- Department of Clinical Sciences, Faculty of Veterinary Science, Bu-Ali Sina University, Hamedan, Iran
| | - Ali Kalantari-Hesari
- Department of Clinical Sciences, Faculty of Veterinary Science, Bu-Ali Sina University, Hamedan, Iran
| | - Iraj Alipourfard
- Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia, Bankowa 9, 40-007 Katow, Poland
| | - Fatemeh Mirzaei
- Department of Anatomical Sciences, School of Medicine, Hamedan University of Medical Sciences, Hamedan, Iran
| | - Sahar Yarahmadi
- Department of Biochemistry, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Elham Bahreini
- Department of Biochemistry, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
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30
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Haythorne E, Lloyd M, Walsby-Tickle J, Tarasov AI, Sandbrink J, Portillo I, Exposito RT, Sachse G, Cyranka M, Rohm M, Rorsman P, McCullagh J, Ashcroft FM. Altered glycolysis triggers impaired mitochondrial metabolism and mTORC1 activation in diabetic β-cells. Nat Commun 2022; 13:6754. [PMID: 36376280 PMCID: PMC9663558 DOI: 10.1038/s41467-022-34095-x] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 10/13/2022] [Indexed: 11/16/2022] Open
Abstract
Chronic hyperglycaemia causes a dramatic decrease in mitochondrial metabolism and insulin content in pancreatic β-cells. This underlies the progressive decline in β-cell function in diabetes. However, the molecular mechanisms by which hyperglycaemia produces these effects remain unresolved. Using isolated islets and INS-1 cells, we show here that one or more glycolytic metabolites downstream of phosphofructokinase and upstream of GAPDH mediates the effects of chronic hyperglycemia. This metabolite stimulates marked upregulation of mTORC1 and concomitant downregulation of AMPK. Increased mTORC1 activity causes inhibition of pyruvate dehydrogenase which reduces pyruvate entry into the tricarboxylic acid cycle and partially accounts for the hyperglycaemia-induced reduction in oxidative phosphorylation and insulin secretion. In addition, hyperglycaemia (or diabetes) dramatically inhibits GAPDH activity, thereby impairing glucose metabolism. Our data also reveal that restricting glucose metabolism during hyperglycaemia prevents these changes and thus may be of therapeutic benefit. In summary, we have identified a pathway by which chronic hyperglycaemia reduces β-cell function.
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Affiliation(s)
- Elizabeth Haythorne
- Department of Physiology, Anatomy and Genetics and OXION, University of Oxford, Parks Road, Oxford, OX1 3PT, UK.
| | - Matthew Lloyd
- Department of Physiology, Anatomy and Genetics and OXION, University of Oxford, Parks Road, Oxford, OX1 3PT, UK
| | - John Walsby-Tickle
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, UK
| | - Andrei I Tarasov
- School of Biomedical Sciences, Ulster University, Coleraine, BT52 1SA, Northern Ireland, UK
| | - Jonas Sandbrink
- Department of Physiology, Anatomy and Genetics and OXION, University of Oxford, Parks Road, Oxford, OX1 3PT, UK
| | - Idoia Portillo
- Department of Physiology, Anatomy and Genetics and OXION, University of Oxford, Parks Road, Oxford, OX1 3PT, UK
| | - Raul Terron Exposito
- Department of Physiology, Anatomy and Genetics and OXION, University of Oxford, Parks Road, Oxford, OX1 3PT, UK
- Institute for Diabetes and Cancer (IDC), Helmholtz Center, Munich, Neuherberg, 85764, Germany
| | - Gregor Sachse
- Department of Physiology, Anatomy and Genetics and OXION, University of Oxford, Parks Road, Oxford, OX1 3PT, UK
- Brandenburg Medical School (Theodor Fontane), ZTM-BB, Brandenburg a. d. H, 14770, Germany
| | - Malgorzata Cyranka
- Department of Physiology, Anatomy and Genetics and OXION, University of Oxford, Parks Road, Oxford, OX1 3PT, UK
| | - Maria Rohm
- Department of Physiology, Anatomy and Genetics and OXION, University of Oxford, Parks Road, Oxford, OX1 3PT, UK
- Institute for Diabetes and Cancer (IDC), Helmholtz Center, Munich, Neuherberg, 85764, Germany
| | - Patrik Rorsman
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, OX3 7LJ, UK
| | - James McCullagh
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, UK
| | - Frances M Ashcroft
- Department of Physiology, Anatomy and Genetics and OXION, University of Oxford, Parks Road, Oxford, OX1 3PT, UK.
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31
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Lactate Activates AMPK Remodeling of the Cellular Metabolic Profile and Promotes the Proliferation and Differentiation of C2C12 Myoblasts. Int J Mol Sci 2022; 23:ijms232213996. [PMID: 36430479 PMCID: PMC9694550 DOI: 10.3390/ijms232213996] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 11/02/2022] [Accepted: 11/10/2022] [Indexed: 11/16/2022] Open
Abstract
Lactate is a general compound fuel serving as the fulcrum of metabolism, which is produced from glycolysis and shuttles between different cells, tissues and organs. Lactate is usually accumulated abundantly in muscles during exercise. It remains unclear whether lactate plays an important role in the metabolism of muscle cells. In this research, we assessed the effects of lactate on myoblasts and clarified the underlying metabolic mechanisms through NMR-based metabonomic profiling. Lactate treatment promoted the proliferation and differentiation of myoblasts, as indicated by significantly enhanced expression levels of the proteins related to cellular proliferation and differentiation, including p-AKT, p-ERK, MyoD and myogenin. Moreover, lactate treatment profoundly regulated metabolisms in myoblasts by promoting the intake and intracellular utilization of lactate, activating the TCA cycle, and thereby increasing energy production. For the first time, we found that lactate treatment evidently promotes AMPK signaling as reflected by the elevated expression levels of p-AMPK and p-ACC. Our results showed that lactate as a metabolic regulator activates AMPK, remodeling the cellular metabolic profile, and thereby promoting the proliferation and differentiation of myoblasts. This study elucidates molecular mechanisms underlying the effects of lactate on skeletal muscle in vitro and may be of benefit to the exploration of lactate acting as a metabolic regulator.
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Azzarello F, Pesce L, De Lorenzi V, Ferri G, Tesi M, Del Guerra S, Marchetti P, Cardarelli F. Single-cell imaging of α and β cell metabolic response to glucose in living human Langerhans islets. Commun Biol 2022; 5:1232. [PMID: 36371562 PMCID: PMC9653440 DOI: 10.1038/s42003-022-04215-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 11/02/2022] [Indexed: 11/13/2022] Open
Abstract
Here we use a combination of two-photon Fluorescence Lifetime Imaging Microscopy (FLIM) of NAD(P)H free/bound ratio in living HIs with post-fixation, immunofluorescence-based, cell-type identification. FLIM allowed to measure variations in the NAD(P)H free/bound ratio induced by glucose; immunofluorescence data allowed to identify single α and β cells; finally, matching of the two datasets allowed to assign metabolic shifts to cell identity. 312 α and 654 β cells from a cohort of 4 healthy donors, 15 total islets, were measured. Both α and β cells display a wide spectrum of responses, towards either an increase or a decrease in NAD(P)H free/bound ratio. Yet, if single-cell data are averaged according to the respective donor and correlated to donor insulin secretion power, a non-random distribution of metabolic shifts emerges: robust average responses of both α and β cells towards an increase of enzyme-bound NAD(P)H belong to the donor with the lowest insulin-secretion power; by contrast, discordant responses, with α cells shifting towards an increase of free NAD(P)H and β cells towards an increase of enzyme-bound NAD(P)H, correspond to the donor with the highest insulin-secretion power. Overall, data reveal neat anti-correlation of tissue metabolic responses with respect to tissue insulin secretion power. A combination of live imaging and immunofluorescence on donor islet cells uncover an anti-correlation of enzyme-bound NAD(P)H and insulin secretion power.
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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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Mukai E, Fujimoto S, Inagaki N. Role of Reactive Oxygen Species in Glucose Metabolism Disorder in Diabetic Pancreatic β-Cells. Biomolecules 2022; 12:biom12091228. [PMID: 36139067 PMCID: PMC9496160 DOI: 10.3390/biom12091228] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 08/28/2022] [Accepted: 08/31/2022] [Indexed: 11/18/2022] Open
Abstract
The dysfunction of pancreatic β-cells plays a central role in the onset and progression of type 2 diabetes mellitus (T2DM). Insulin secretory defects in β-cells are characterized by a selective impairment of glucose stimulation, and a reduction in glucose-induced ATP production, which is essential for insulin secretion. High glucose metabolism for insulin secretion generates reactive oxygen species (ROS) in mitochondria. In addition, the expression of antioxidant enzymes is very low in β-cells. Therefore, β-cells are easily exposed to oxidative stress. In islet studies using a nonobese T2DM animal model that exhibits selective impairment of glucose-induced insulin secretion (GSIS), quenching ROS generated by glucose stimulation and accumulated under glucose toxicity can improve impaired GSIS. Acute ROS generation and toxicity cause glucose metabolism disorders through different molecular mechanisms. Nuclear factor erythroid 2-related factor 2 (Nrf2), a transcription factor, is a master regulator of antioxidant defense and a potential therapeutic target in oxidative stress-related diseases, suggesting the possible involvement of Nrf2 in β-cell dysfunction caused by ROS. In this review, we describe the mechanisms of insulin secretory defects induced by oxidative stress in diabetic β-cells.
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Affiliation(s)
- Eri Mukai
- Medical Physiology and Metabolism Laboratory, Department of Biomedical Sciences, College of Life Sciences, Ritsumeikan University, Kusatsu 5258577, Japan
- Correspondence:
| | - Shimpei Fujimoto
- Department of Endocrinology, Metabolism, and Nephrology, Kochi Medical School, Kochi University, Kochi 7838505, Japan
| | - Nobuya Inagaki
- Department of Diabetes, Endocrinology and Nutrition, Graduate School of Medicine, Kyoto University, Kyoto 6068507, Japan
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Fets L, Bevan N, Nunes PM, Campos S, Dos Santos MS, Sherriff E, MacRae JI, House D, Anastasiou D. MOG analogues to explore the MCT2 pharmacophore, α-ketoglutarate biology and cellular effects of N-oxalylglycine. Commun Biol 2022; 5:877. [PMID: 36028752 PMCID: PMC9418262 DOI: 10.1038/s42003-022-03805-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 08/05/2022] [Indexed: 11/09/2022] Open
Abstract
α-ketoglutarate (αKG) is a central metabolic node with a broad influence on cellular physiology. The αKG analogue N-oxalylglycine (NOG) and its membrane-permeable pro-drug derivative dimethyl-oxalylglycine (DMOG) have been extensively used as tools to study prolyl hydroxylases (PHDs) and other αKG-dependent processes. In cell culture media, DMOG is rapidly converted to MOG, which enters cells through monocarboxylate transporter MCT2, leading to intracellular NOG concentrations that are sufficiently high to inhibit glutaminolysis enzymes and cause cytotoxicity. Therefore, the degree of (D)MOG instability together with MCT2 expression levels determine the intracellular targets NOG engages with and, ultimately, its effects on cell viability. Here we designed and characterised a series of MOG analogues with the aims of improving compound stability and exploring the functional requirements for interaction with MCT2, a relatively understudied member of the SLC16 family. We report MOG analogues that maintain ability to enter cells via MCT2, and identify compounds that do not inhibit glutaminolysis or cause cytotoxicity but can still inhibit PHDs. We use these analogues to show that, under our experimental conditions, glutaminolysis-induced activation of mTORC1 can be uncoupled from PHD activity. Therefore, these new compounds can help deconvolute cellular effects that result from the polypharmacological action of NOG.
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Affiliation(s)
- Louise Fets
- Cancer Metabolism Laboratory, The Francis Crick Institute, London, UK
- Drug Transport and Tumour Metabolism Lab, MRC London Institute of Medical Sciences, London, UK
| | - Natalie Bevan
- Cancer Metabolism Laboratory, The Francis Crick Institute, London, UK
| | - Patrícia M Nunes
- Cancer Metabolism Laboratory, The Francis Crick Institute, London, UK
| | | | | | | | - James I MacRae
- Metabolomics Science Technology Platform, The Francis Crick Institute, London, UK
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Huang K, Liang Y, Wang K, Wu J, Luo H, Yi B. Influence of circulating nesfatin-1, GSH and SOD on insulin secretion in the development of T2DM. Front Public Health 2022; 10:882686. [PMID: 36045734 PMCID: PMC9421132 DOI: 10.3389/fpubh.2022.882686] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 07/18/2022] [Indexed: 01/21/2023] Open
Abstract
Aims To evaluate the correlation of nesfatin-1, GSH and SOD levels with β-cell insulin secretion and their influence on insulin secretion in the development of type 2 diabetes mellitus (T2DM). Materials and methods 75 patients with T2DM, 67 with prediabetes and 37 heathy participants were recruited in this study. Serum levels of nesfatin-1, GSH and SOD were quantified and statistically analyzed. Results The levels of nesfatin-1, GSH and SOD in T2DM were significantly decreased (P < 0.001) compared to either in prediabetes or in healthy control, and significant reduction of these biomarkers was also observed in prediabetes when compared to the control (P < 0.001). Circulating nesfatin-1, GSH and SOD were not only strongly correlated with β-cell insulin secretion, but also exerted remarkable influence on the secretion. Conclusion Serum nesfatin-1, GSH and SOD are important factors involving insulin secretion in the development of T2DM, which may help provide new ideas for forthcoming investigations on the roles of these factors in pathogenesis of T2DM, as well as for active prediction and prevention of prediabetes before it develops into overt T2DM.
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Affiliation(s)
- Kangkang Huang
- Department of Clinical Laboratory, Xiangya Hospital, Central South University, Changsha, China,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Yunlai Liang
- Department of Clinical Laboratory, Xiangya Hospital, Central South University, Changsha, China
| | - Kun Wang
- Department of Clinical Laboratory, Xiangya Hospital, Central South University, Changsha, China
| | - Jiahui Wu
- Department of Clinical Laboratory, Xiangya Hospital, Central South University, Changsha, China,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Huidan Luo
- Department of Clinical Laboratory, Xiangya Hospital, Central South University, Changsha, China,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Bin Yi
- Department of Clinical Laboratory, Xiangya Hospital, Central South University, Changsha, China,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China,*Correspondence: Bin Yi
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He T, Ma J, Mahfuz S, Zheng Y, Long S, Wang J, Wu D, Piao X. Dietary live yeast supplementation alleviates transport-stress-impaired meat quality of broilers through maintaining muscle energy metabolism and antioxidant status. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2022; 102:4086-4096. [PMID: 34997593 PMCID: PMC9302652 DOI: 10.1002/jsfa.11758] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 12/22/2021] [Accepted: 01/08/2021] [Indexed: 06/14/2023]
Abstract
BACKGROUND This experiment was to investigate the effect of dietary live yeast (LY, 1 × 1010 CFU g-1 ) supplementation on serum metabolic parameters, meat quality as well as antioxidant enzyme activity of transported broilers. A total of 192 one-day-old broilers were randomly assigned to four treatments with six replicates and eight chicks per replicate: a basal diet without transportation (CON), a basal diet containing 0 (T), 500 (T + LY500 ) and 1000 mg kg-1 (T + LY1000 ) LY with 3 h of transportation after feeding for 42 days, respectively. The serum and muscle samples of broilers were collected immediately after 3 h of transportation. RESULTS A higher (P < 0.05) final body weight and average daily weight gain were observed in T + LY1000 group compared with CON and T groups. The T + LY1000 group reduced (P < 0.05) the serum lactate contents and improved (P < 0.05) the pH24h and decreased (P < 0.05) the drip loss in muscles of transported-broilers. Also, the T + LY1000 group enhanced (P < 0.05) the total-antioxidant capacity and reduced (P < 0.05) the malondialdehyde in serum and muscles. Besides, the messenger RNA (mRNA) expression of avian uncoupling protein (avUCP) in muscles was down-regulated (P < 0.05) of T + LY1000 group compared with T group. CONCLUSION Dietary LY supplementation alleviates transport-stress-impaired meat quality of broilers through maintaining muscle energy metabolism and antioxidant status. Therefore, LY may serve as a potential protector for broilers under transport stress in the future. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- Tengfei He
- State Key Laboratory of Animal Nutrition, College of Animal Science and TechnologyChina Agricultural UniversityBeijingChina
| | - Jiayu Ma
- State Key Laboratory of Animal Nutrition, College of Animal Science and TechnologyChina Agricultural UniversityBeijingChina
| | - Shad Mahfuz
- State Key Laboratory of Animal Nutrition, College of Animal Science and TechnologyChina Agricultural UniversityBeijingChina
- Department of Animal NutritionSylhet Agricultural UniversitySylhetBangladesh
| | - Yuhui Zheng
- State Key Laboratory of Animal Nutrition, College of Animal Science and TechnologyChina Agricultural UniversityBeijingChina
| | - Shenfei Long
- State Key Laboratory of Animal Nutrition, College of Animal Science and TechnologyChina Agricultural UniversityBeijingChina
| | - Jian Wang
- State Key Laboratory of Animal Nutrition, College of Animal Science and TechnologyChina Agricultural UniversityBeijingChina
| | - Di Wu
- State Key Laboratory of Animal Nutrition, College of Animal Science and TechnologyChina Agricultural UniversityBeijingChina
| | - Xiangshu Piao
- State Key Laboratory of Animal Nutrition, College of Animal Science and TechnologyChina Agricultural UniversityBeijingChina
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Lv C, Sun Y, Zhang ZY, Aboelela Z, Qiu X, Meng ZX. β-cell dynamics in type 2 diabetes and in dietary and exercise interventions. J Mol Cell Biol 2022; 14:6656373. [PMID: 35929791 PMCID: PMC9710517 DOI: 10.1093/jmcb/mjac046] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 05/07/2022] [Accepted: 08/03/2022] [Indexed: 01/14/2023] Open
Abstract
Pancreatic β-cell dysfunction and insulin resistance are two of the major causes of type 2 diabetes (T2D). Recent clinical and experimental studies have suggested that the functional capacity of β-cells, particularly in the first phase of insulin secretion, is a primary contributor to the progression of T2D and its associated complications. Pancreatic β-cells undergo dynamic compensation and decompensation processes during the development of T2D, in which metabolic stresses such as endoplasmic reticulum stress, oxidative stress, and inflammatory signals are key regulators of β-cell dynamics. Dietary and exercise interventions have been shown to be effective approaches for the treatment of obesity and T2D, especially in the early stages. Whilst the targeted tissues and underlying mechanisms of dietary and exercise interventions remain somewhat vague, accumulating evidence has implicated the improvement of β-cell functional capacity. In this review, we summarize recent advances in the understanding of the dynamic adaptations of β-cell function in T2D progression and clarify the effects and mechanisms of dietary and exercise interventions on β-cell dysfunction in T2D. This review provides molecular insights into the therapeutic effects of dietary and exercise interventions on T2D, and more importantly, it paves the way for future research on the related underlying mechanisms for developing precision prevention and treatment of T2D.
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Affiliation(s)
- Chengan Lv
- Department of Pathology and Pathophysiology and Metabolic Research Center of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China,Key Laboratory of Disease Proteomics of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Yuchen Sun
- Department of Pathology and Pathophysiology and Metabolic Research Center of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China,Key Laboratory of Disease Proteomics of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China,Zhejiang University–University of Edinburgh Institute (ZJE), Zhejiang University, Haining 314400, China
| | - Zhe Yu Zhang
- Department of Pathology and Pathophysiology and Metabolic Research Center of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China,Key Laboratory of Disease Proteomics of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Zeyad Aboelela
- Department of Pathology and Pathophysiology and Metabolic Research Center of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China,Key Laboratory of Disease Proteomics of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China,Bachelors of Surgery, Bachelors of Medicine (MBBS), Zhejiang University School of Medicine, Hangzhou 310003, China
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Monitoring glycolytic dynamics in single cells using a fluorescent biosensor for fructose 1,6-bisphosphate. Proc Natl Acad Sci U S A 2022; 119:e2204407119. [PMID: 35881794 PMCID: PMC9351453 DOI: 10.1073/pnas.2204407119] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Cellular metabolism is regulated over space and time to ensure that energy production is efficiently matched with consumption. Fluorescent biosensors are useful tools for studying metabolism as they enable real-time detection of metabolite abundance with single-cell resolution. For monitoring glycolysis, the intermediate fructose 1,6-bisphosphate (FBP) is a particularly informative signal as its concentration is strongly correlated with flux through the whole pathway. Using GFP insertion into the ligand-binding domain of the Bacillus subtilis transcriptional regulator CggR, we developed a fluorescent biosensor for FBP termed HYlight. We demonstrate that HYlight can reliably report the real-time dynamics of glycolysis in living cells and tissues, driven by various metabolic or pharmacological perturbations, alone or in combination with other physiologically relevant signals. Using this sensor, we uncovered previously unknown aspects of β-cell glycolytic heterogeneity and dynamics.
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Merrins MJ, Corkey BE, Kibbey RG, Prentki M. 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: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [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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Affiliation(s)
- Matthew J Merrins
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Wisconsin-Madison, Madison, WI, USA; William S. Middleton Memorial Veterans Hospital, Madison, WI, USA.
| | - Barbara E Corkey
- Department of Medicine, Boston University School of Medicine, Boston, MA, USA.
| | - Richard G Kibbey
- Departments of Internal Medicine (Endocrinology) and Cellular & Molecular Physiology, Yale University, New Haven, CT, USA.
| | - Marc Prentki
- Molecular Nutrition Unit and Montreal Diabetes Research Center, CRCHUM, and Departments of Nutrition, Biochemistry and Molecular Medicine, Université de Montréal, Montréal, ON, Canada.
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Ishihara H. Metabolism-secretion coupling in glucose-stimulated insulin secretion. Diabetol Int 2022; 13:463-470. [PMID: 35693987 PMCID: PMC9174369 DOI: 10.1007/s13340-022-00576-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Accepted: 02/27/2022] [Indexed: 01/09/2023]
Abstract
Pancreatic β-cells in the islets of Langerhans secrete insulin in response to blood glucose levels. Precise control of the amount of insulin secreted is of critical importance for maintaining systemic carbohydrate homeostasis. It is now well established that glucose induced production of ATP from ADP and the KATP channel closure elevate cytosolic Ca2+, triggering insulin exocytosis in β-cells. However, for full activation of insulin secretion by glucose, other mechanisms besides Ca2+ elevation are needed. These mechanisms are the targets of current research and include intracellular metabolic pathways branching from glycolysis. They are metabolic pathways originating from the TCA cycle intermediates, the glycerolipid/free fatty acid cycle and the pentose phosphate pathway. Signaling effects of these pathways including degradation (removal) of protein SUMOylation, modulation of insulin vesicular energetics, and lipid modulation of exocytotic machinery may converge to fulfill insulin secretion, though the precise mechanisms have yet to be elucidated. This mini-review summarize recent advances in research on metabolic coupling mechanisms functioning in insulin secretion.
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Affiliation(s)
- Hisamitsu Ishihara
- Division of Diabetes and Metabolism, Nihon University School of Medicine, 30-1 Oyaguchi-kamicho, Itabashi-ku, Tokyo, 173-8610 Japan
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Diane A, Al-Shukri NA, Bin Abdul Mu-U-Min R, Al-Siddiqi HH. β-cell mitochondria in diabetes mellitus: a missing puzzle piece in the generation of hPSC-derived pancreatic β-cells? J Transl Med 2022; 20:163. [PMID: 35397560 PMCID: PMC8994301 DOI: 10.1186/s12967-022-03327-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 03/01/2022] [Indexed: 11/28/2022] Open
Abstract
Diabetes mellitus (DM), currently affecting 463 million people worldwide is a chronic disease characterized by impaired glucose metabolism resulting from the loss or dysfunction of pancreatic β-cells with the former preponderating in type 1 diabetes (T1DM) and the latter in type 2 diabetes (T2DM). Because impaired insulin secretion due to dysfunction or loss of pancreatic β-cells underlies different types of diabetes, research has focused its effort towards the generation of pancreatic β-cells from human pluripotent stem cell (hPSC) as a potential source of cells to compensate for insulin deficiency. However, many protocols developed to differentiate hPSCs into insulin-expressing β-cells in vitro have generated hPSC-derived β-cells with either immature phenotype such as impaired glucose-stimulated insulin secretion (GSIS) or a weaker response to GSIS than cadaveric islets. In pancreatic β-cells, mitochondria play a central role in coupling glucose metabolism to insulin exocytosis, thereby ensuring refined control of GSIS. Defects in β-cell mitochondrial metabolism and function impair this metabolic coupling. In the present review, we highlight the role of mitochondria in metabolism secretion coupling in the β-cells and summarize the evidence accumulated for the implication of mitochondria in β-cell dysfunction in DM and consequently, how targeting mitochondria function might be a new and interesting strategy to further perfect the differentiation protocol for generation of mature and functional hPSC-derived β-cells with GSIS profile similar to human cadaveric islets for drug screening or potentially for cell therapy.
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Affiliation(s)
- Abdoulaye Diane
- Diabetes Research Center, Qatar Biomedical Research Institute (QBRI), Hamad Bin Khalifa University (HBKU), Qatar Foundation (QF), Doha, Qatar.
| | - Noora Ali Al-Shukri
- Diabetes Research Center, Qatar Biomedical Research Institute (QBRI), Hamad Bin Khalifa University (HBKU), Qatar Foundation (QF), Doha, Qatar
| | - Razik Bin Abdul Mu-U-Min
- Diabetes Research Center, Qatar Biomedical Research Institute (QBRI), Hamad Bin Khalifa University (HBKU), Qatar Foundation (QF), Doha, Qatar
| | - Heba H Al-Siddiqi
- Diabetes Research Center, Qatar Biomedical Research Institute (QBRI), Hamad Bin Khalifa University (HBKU), Qatar Foundation (QF), Doha, Qatar
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Khan D, Moffett RC, Flatt PR, Tarasov AI. Classical and non-classical islet peptides in the control of β-cell function. Peptides 2022; 150:170715. [PMID: 34958851 DOI: 10.1016/j.peptides.2021.170715] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 11/25/2021] [Accepted: 12/17/2021] [Indexed: 12/25/2022]
Abstract
The dual role of the pancreas as both an endocrine and exocrine gland is vital for food digestion and control of nutrient metabolism. The exocrine pancreas secretes enzymes into the small intestine aiding digestion of sugars and fats, whereas the endocrine pancreas secretes a cocktail of hormones into the blood, which is responsible for blood glucose control and regulation of carbohydrate, protein and fat metabolism. Classical islet hormones, insulin, glucagon, pancreatic polypeptide and somatostatin, interact in an autocrine and paracrine manner, to fine-tube the islet function and insulin secretion to the needs of the body. Recently pancreatic islets have been reported to express a number of non-classical peptide hormones involved in metabolic signalling, whose major production site was believed to reside outside pancreas, e.g. in the small intestine. We highlight the key non-classical islet peptides, and consider their involvement, together with established islet hormones, in regulation of stimulus-secretion coupling as well as proliferation, survival and transdifferentiation of β-cells. We furthermore focus on the paracrine interaction between classical and non-classical islet hormones in the maintenance of β-cell function. Understanding the functional relationships between these islet peptides might help to develop novel, more efficient treatments for diabetes and related metabolic disorders.
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Affiliation(s)
- Dawood Khan
- Biomedical Sciences Research Institute, School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland, UK.
| | - R Charlotte Moffett
- Biomedical Sciences Research Institute, School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland, UK
| | - Peter R Flatt
- Biomedical Sciences Research Institute, School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland, UK
| | - Andrei I Tarasov
- Biomedical Sciences Research Institute, School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland, UK
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Mechanisms Underlying the Expansion and Functional Maturation of β-Cells in Newborns: Impact of the Nutritional Environment. Int J Mol Sci 2022; 23:ijms23042096. [PMID: 35216239 PMCID: PMC8877060 DOI: 10.3390/ijms23042096] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 02/04/2022] [Accepted: 02/09/2022] [Indexed: 12/24/2022] Open
Abstract
The functional maturation of insulin-secreting β-cells is initiated before birth and is completed in early postnatal life. This process has a critical impact on the acquisition of an adequate functional β-cell mass and on the capacity to meet and adapt to insulin needs later in life. Many cellular pathways playing a role in postnatal β-cell development have already been identified. However, single-cell transcriptomic and proteomic analyses continue to reveal new players contributing to the acquisition of β-cell identity. In this review, we provide an updated picture of the mechanisms governing postnatal β-cell mass expansion and the transition of insulin-secreting cells from an immature to a mature state. We then highlight the contribution of the environment to β-cell maturation and discuss the adverse impact of an in utero and neonatal environment characterized by calorie and fat overload or by protein deficiency and undernutrition. Inappropriate nutrition early in life constitutes a risk factor for developing diabetes in adulthood and can affect the β-cells of the offspring over two generations. A better understanding of these events occurring in the neonatal period will help developing better strategies to produce functional β-cells and to design novel therapeutic approaches for the prevention and treatment of diabetes.
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45
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Tentonin 3/TMEM150C regulates glucose-stimulated insulin secretion in pancreatic β-cells. Cell Rep 2021; 37:110067. [PMID: 34852221 DOI: 10.1016/j.celrep.2021.110067] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 10/17/2021] [Accepted: 11/08/2021] [Indexed: 11/24/2022] Open
Abstract
Glucose homeostasis is initially regulated by the pancreatic hormone insulin. Glucose-stimulated insulin secretion in β-cells is composed of two cellular mechanisms: a high glucose concentration not only depolarizes the membrane potential of the β-cells by ATP-sensitive K+ channels but also induces cell inflation, which is sufficient to release insulin granules. However, the molecular identity of the stretch-activated cation channel responsible for the latter pathway remains unknown. Here, we demonstrate that Tentonin 3/TMEM150C (TTN3), a mechanosensitive channel, contributes to glucose-stimulated insulin secretion by mediating cation influx. TTN3 is expressed specifically in β-cells and mediates cation currents to glucose and hypotonic stimulations. The glucose-induced depolarization, firing activity, and Ca2+ influx of β-cells were significantly lower in Ttn3-/- mice. More importantly, Ttn3-/- mice show impaired glucose tolerance with decreased insulin secretion in vivo. We propose that TTN3, as a stretch-activated cation channel, contributes to glucose-stimulated insulin secretion.
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Karagiannis A, Gallopin T, Lacroix A, Plaisier F, Piquet J, Geoffroy H, Hepp R, Naudé J, Le Gac B, Egger R, Lambolez B, Li D, Rossier J, Staiger JF, Imamura H, Seino S, Roeper J, Cauli B. Lactate is an energy substrate for rodent cortical neurons and enhances their firing activity. eLife 2021; 10:e71424. [PMID: 34766906 PMCID: PMC8651295 DOI: 10.7554/elife.71424] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 11/09/2021] [Indexed: 12/12/2022] Open
Abstract
Glucose is the mandatory fuel for the brain, yet the relative contribution of glucose and lactate for neuronal energy metabolism is unclear. We found that increased lactate, but not glucose concentration, enhances the spiking activity of neurons of the cerebral cortex. Enhanced spiking was dependent on ATP-sensitive potassium (KATP) channels formed with KCNJ11 and ABCC8 subunits, which we show are functionally expressed in most neocortical neuronal types. We also demonstrate the ability of cortical neurons to take-up and metabolize lactate. We further reveal that ATP is produced by cortical neurons largely via oxidative phosphorylation and only modestly by glycolysis. Our data demonstrate that in active neurons, lactate is preferred to glucose as an energy substrate, and that lactate metabolism shapes neuronal activity in the neocortex through KATP channels. Our results highlight the importance of metabolic crosstalk between neurons and astrocytes for brain function.
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Affiliation(s)
- Anastassios Karagiannis
- Sorbonne Université, CNRS, INSERM, Neurosciences Paris Seine - Institut de Biologie Paris Seine (NPS-IBPS)ParisFrance
| | - Thierry Gallopin
- Brain Plasticity Unit, CNRS UMR 8249, CNRS, ESPCI ParisParisFrance
| | - Alexandre Lacroix
- Sorbonne Université, CNRS, INSERM, Neurosciences Paris Seine - Institut de Biologie Paris Seine (NPS-IBPS)ParisFrance
| | - Fabrice Plaisier
- Sorbonne Université, CNRS, INSERM, Neurosciences Paris Seine - Institut de Biologie Paris Seine (NPS-IBPS)ParisFrance
| | - Juliette Piquet
- Sorbonne Université, CNRS, INSERM, Neurosciences Paris Seine - Institut de Biologie Paris Seine (NPS-IBPS)ParisFrance
| | - Hélène Geoffroy
- Brain Plasticity Unit, CNRS UMR 8249, CNRS, ESPCI ParisParisFrance
| | - Régine Hepp
- Sorbonne Université, CNRS, INSERM, Neurosciences Paris Seine - Institut de Biologie Paris Seine (NPS-IBPS)ParisFrance
| | - Jérémie Naudé
- Sorbonne Université, CNRS, INSERM, Neurosciences Paris Seine - Institut de Biologie Paris Seine (NPS-IBPS)ParisFrance
| | - Benjamin Le Gac
- Sorbonne Université, CNRS, INSERM, Neurosciences Paris Seine - Institut de Biologie Paris Seine (NPS-IBPS)ParisFrance
| | - Richard Egger
- Institute for Neurophysiology, Goethe University FrankfurtFrankfurtGermany
| | - Bertrand Lambolez
- Sorbonne Université, CNRS, INSERM, Neurosciences Paris Seine - Institut de Biologie Paris Seine (NPS-IBPS)ParisFrance
| | - Dongdong Li
- Sorbonne Université, CNRS, INSERM, Neurosciences Paris Seine - Institut de Biologie Paris Seine (NPS-IBPS)ParisFrance
| | - Jean Rossier
- Sorbonne Université, CNRS, INSERM, Neurosciences Paris Seine - Institut de Biologie Paris Seine (NPS-IBPS)ParisFrance
- Brain Plasticity Unit, CNRS UMR 8249, CNRS, ESPCI ParisParisFrance
| | - Jochen F Staiger
- Institute for Neuroanatomy, University Medical Center Göttingen, Georg-August- University GöttingenGoettingenGermany
| | - Hiromi Imamura
- Graduate School of Biostudies, Kyoto UniversityKyotoJapan
| | - Susumu Seino
- Division of Molecular and Metabolic Medicine, Kobe University Graduate School of MedicineHyogoJapan
| | - Jochen Roeper
- Institute for Neurophysiology, Goethe University FrankfurtFrankfurtGermany
| | - Bruno Cauli
- Sorbonne Université, CNRS, INSERM, Neurosciences Paris Seine - Institut de Biologie Paris Seine (NPS-IBPS)ParisFrance
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Chen SM, Hee SW, Chou SY, Liu MW, Chen CH, Mochly-Rosen D, Chang TJ, Chuang LM. Activation of Aldehyde Dehydrogenase 2 Ameliorates Glucolipotoxicity of Pancreatic Beta Cells. Biomolecules 2021; 11:biom11101474. [PMID: 34680107 PMCID: PMC8533366 DOI: 10.3390/biom11101474] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 09/28/2021] [Accepted: 09/29/2021] [Indexed: 01/12/2023] Open
Abstract
Chronic hyperglycemia and hyperlipidemia hamper beta cell function, leading to glucolipotoxicity. Mitochondrial aldehyde dehydrogenase 2 (ALDH2) detoxifies reactive aldehydes, such as methylglyoxal (MG) and 4-hydroxynonenal (4-HNE), derived from glucose and lipids, respectively. We aimed to investigate whether ALDH2 activators ameliorated beta cell dysfunction and apoptosis induced by glucolipotoxicity, and its potential mechanisms of action. Glucose-stimulated insulin secretion (GSIS) in MIN6 cells and insulin secretion from isolated islets in perifusion experiments were measured. The intracellular ATP concentrations and oxygen consumption rates of MIN6 cells were assessed. Furthermore, the cell viability, apoptosis, and mitochondrial and intracellular reactive oxygen species (ROS) levels were determined. Additionally, the pro-apoptotic, apoptotic, and anti-apoptotic signaling pathways were investigated. We found that Alda-1 enhanced GSIS by improving the mitochondrial function of pancreatic beta cells. Alda-1 rescued MIN6 cells from MG- and 4-HNE-induced beta cell death, apoptosis, mitochondrial dysfunction, and ROS production. However, the above effects of Alda-1 were abolished in Aldh2 knockdown MIN6 cells. In conclusion, we reported that the activator of ALDH2 not only enhanced GSIS, but also ameliorated the glucolipotoxicity of beta cells by reducing both the mitochondrial and intracellular ROS levels, thereby improving mitochondrial function, restoring beta cell function, and protecting beta cells from apoptosis and death.
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Affiliation(s)
- Shiau-Mei Chen
- Department of Internal Medicine, National Taiwan University Hospital, Taipei 100, Taiwan; (S.-M.C.); (S.-W.H.); (S.-Y.C.); (M.-W.L.); (L.-M.C.)
| | - Siow-Wey Hee
- Department of Internal Medicine, National Taiwan University Hospital, Taipei 100, Taiwan; (S.-M.C.); (S.-W.H.); (S.-Y.C.); (M.-W.L.); (L.-M.C.)
| | - Shih-Yun Chou
- Department of Internal Medicine, National Taiwan University Hospital, Taipei 100, Taiwan; (S.-M.C.); (S.-W.H.); (S.-Y.C.); (M.-W.L.); (L.-M.C.)
| | - Meng-Wei Liu
- Department of Internal Medicine, National Taiwan University Hospital, Taipei 100, Taiwan; (S.-M.C.); (S.-W.H.); (S.-Y.C.); (M.-W.L.); (L.-M.C.)
| | - Che-Hong Chen
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA; (C.-H.C.); (D.M.-R.)
| | - Daria Mochly-Rosen
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA; (C.-H.C.); (D.M.-R.)
| | - Tien-Jyun Chang
- Department of Internal Medicine, National Taiwan University Hospital, Taipei 100, Taiwan; (S.-M.C.); (S.-W.H.); (S.-Y.C.); (M.-W.L.); (L.-M.C.)
- School of Medicine, College of Medicine, National Taiwan University, Taipei 100, Taiwan
- Correspondence: ; Tel.: +886-2-23123456 (ext. 66217)
| | - Lee-Ming Chuang
- Department of Internal Medicine, National Taiwan University Hospital, Taipei 100, Taiwan; (S.-M.C.); (S.-W.H.); (S.-Y.C.); (M.-W.L.); (L.-M.C.)
- School of Medicine, College of Medicine, National Taiwan University, Taipei 100, Taiwan
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Yang J, Hammoud B, Li C, Ridler A, Yau D, Kim J, Won KJ, Stanley CA, Hoshi T, Stanescu DE. Decreased KATP Channel Activity Contributes to the Low Glucose Threshold for Insulin Secretion of Rat Neonatal Islets. Endocrinology 2021; 162:6301135. [PMID: 34134142 PMCID: PMC8276892 DOI: 10.1210/endocr/bqab121] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Indexed: 12/12/2022]
Abstract
Transitional hypoglycemia in normal newborns occurs in the first 3 days of life and has clinical features consistent with hyperinsulinism. We found a lower threshold for glucose-stimulated insulin secretion from freshly isolated embryonic day (E) 22 rat islets, which persisted into the first postnatal days. The threshold reached the adult level by postnatal day (P) 14. Culturing P14 islets also decreased the glucose threshold. Freshly isolated P1 rat islets had a lower threshold for insulin secretion in response to 2-aminobicyclo-(2, 2, 1)-heptane-2-carboxylic acid, a nonmetabolizable leucine analog, and diminished insulin release in response to tolbutamide, an inhibitor of β-cell KATP channels. These findings suggested that decreased KATP channel function could be responsible for the lower glucose threshold for insulin secretion. Single-cell transcriptomic analysis did not reveal a lower expression of KATP subunit genes in E22 compared with P14 β cells. The investigation of electrophysiological characteristics of dispersed β cells showed that early neonatal and cultured cells had fewer functional KATP channels per unit membrane area. Our findings suggest that decreased surface density of KATP channels may contribute to the observed differences in glucose threshold for insulin release.
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Affiliation(s)
- Juxiang Yang
- Division of Endocrinology and Diabetes, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Batoul Hammoud
- Division of Endocrinology and Diabetes, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Changhong Li
- Division of Endocrinology and Diabetes, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Abigail Ridler
- Division of Endocrinology and Diabetes, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Daphne Yau
- Division of Endocrinology and Diabetes, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Junil Kim
- Biotech Research & Innovation Centre, University of Copenhagen, DK-2200 Copenhagen N, Denmark
- School of Systems Biomedical Science, Soongsil University, Seoul 06978, South Korea
| | - Kyoung-Jae Won
- Biotech Research & Innovation Centre, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Charles A Stanley
- Division of Endocrinology and Diabetes, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
- Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Toshinori Hoshi
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Diana E Stanescu
- Division of Endocrinology and Diabetes, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
- Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Correspondence: Diana Elena Stanescu, MD, The Children's Hospital of Philadelphia, Abramson Pediatric Research Center, 3615 Civic Center Blvd, #802G, Philadelphia, PA 19104, USA.
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Metabolic Phenotypes and Step by Step Evolution of Type 2 Diabetes: A New Paradigm. Biomedicines 2021; 9:biomedicines9070800. [PMID: 34356863 PMCID: PMC8301386 DOI: 10.3390/biomedicines9070800] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 07/02/2021] [Accepted: 07/05/2021] [Indexed: 01/18/2023] Open
Abstract
Unlike bolus insulin secretion mechanisms, basal insulin secretion is poorly understood. It is essential to elucidate these mechanisms in non-hyperinsulinaemia healthy persons. This establishes a baseline for investigation into pathologies where these processes are dysregulated, such as in type 2 diabetes (T2DM), cardiovascular disease (CVD), certain cancers and dementias. Chronic hyperinsulinaemia enforces glucose fueling, depleting the NAD+ dependent antioxidant activity that increases mitochondrial reactive oxygen species (mtROS). Consequently, beta-cell mitochondria increase uncoupling protein expression, which decreases the mitochondrial ATP surge generation capacity, impairing bolus mediated insulin exocytosis. Excessive ROS increases the Drp1:Mfn2 ratio, increasing mitochondrial fission, which increases mtROS; endoplasmic reticulum-stress and impaired calcium homeostasis ensues. Healthy individuals in habitual ketosis have significantly lower glucagon and insulin levels than T2DM individuals. As beta-hydroxybutyrate rises, hepatic gluconeogenesis and glycogenolysis supply extra-hepatic glucose needs, and osteocalcin synthesis/release increases. We propose insulin’s primary role is regulating beta-hydroxybutyrate synthesis, while the role of bone regulates glucose uptake sensitivity via osteocalcin. Osteocalcin regulates the alpha-cell glucagon secretory profile via glucagon-like peptide-1 and serotonin, and beta-hydroxybutyrate synthesis via regulating basal insulin levels. Establishing metabolic phenotypes aids in resolving basal insulin secretion regulation, enabling elucidation of the pathological changes that occur and progress into chronic diseases associated with ageing.
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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: 17] [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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