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Fagundes RR, Zaldumbide A, Taylor CT. Role of hypoxia-inducible factor 1 in type 1 diabetes. Trends Pharmacol Sci 2024:S0165-6147(24)00143-3. [PMID: 39127527 DOI: 10.1016/j.tips.2024.07.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2024] [Revised: 07/08/2024] [Accepted: 07/11/2024] [Indexed: 08/12/2024]
Abstract
Type 1 diabetes (T1D) is a common autoimmune disease in which dysregulated glucose metabolism is a key feature. T1D is both poorly understood and in need of improved therapeutics. Hypoxia is frequently encountered in multiple tissues in T1D patients including the pancreas and sites of diabetic complications. Hypoxia-inducible factor (HIF)-1, a ubiquitous master regulator of the adaptive response to hypoxia, promotes glucose metabolism through transcriptional and non-transcriptional mechanisms and alters disease progression in multiple preclinical T1D models. However, how HIF-1 activation in β-cells of the pancreas and immune cells (two key cell types in T1D) ultimately affects disease progression remains controversial. We discuss recent advances in our understanding of the role of hypoxia/HIF-1-induced glycolysis in T1D and explore the possible use of drugs targeting this pathway as potential new therapeutics.
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Affiliation(s)
- Raphael R Fagundes
- Department of Cell and Chemical Biology, Leiden University Medical Center, Albinusdreef 2, Leiden, The Netherlands
| | - Arnaud Zaldumbide
- Department of Cell and Chemical Biology, Leiden University Medical Center, Albinusdreef 2, Leiden, The Netherlands
| | - Cormac T Taylor
- School of Medicine and Conway Institute of Biomolecular and Biomedical Research and Systems Biology Ireland, University College Dublin, Belfield, Dublin 4, Ireland.
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2
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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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3
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Ridout SA, Vellanki P, Nemenman I. A mathematical model for ketosis-prone diabetes suggests the existence of multiple pancreatic β-cell inactivation mechanisms. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.04.597343. [PMID: 38895272 PMCID: PMC11185683 DOI: 10.1101/2024.06.04.597343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
Ketosis-prone diabetes mellitus (KPD) is a subtype of type 2 diabetes, which presents much like type 1 diabetes, with dramatic hyperglycemia and ketoacidosis. Although KPD patients are initially insulin-dependent, after a few months of insulin treatment, ~ 70% undergo near-normoglycemia remission and can maintain blood glucose without insulin, as in early type 2 diabetes or prediabetes. Here, we propose that these phenomena can be explained by the existence of a fast, reversible glucotoxicity process, which may exist in all people but be more pronounced in those susceptible to KPD. We develop a simple mathematical model of the pathogenesis of KPD, which incorporates this assumption, and show that it reproduces the phenomenology of KPD, including variations in the ability for patients to achieve and sustain remission. These results suggest that a variation of our model may be able to quantitatively describe variations in the course of remission among individuals with KPD.
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Affiliation(s)
- Sean A. Ridout
- Department of Physics, Emory University, Atlanta, GA, USA
- Initiative in Theory and Modeling of Living Systems, Emory University, Atlanta, GA, USA
| | - Priyathama Vellanki
- Department of Internal Medicine, Division of Endocrinology, Emory University School of Medicine, Emory University, Atlanta, GA, USA
- Grady Health System, Atlanta, GA, USA
| | - Ilya Nemenman
- Department of Physics, Emory University, Atlanta, GA, USA
- Initiative in Theory and Modeling of Living Systems, Emory University, Atlanta, GA, USA
- Department of Biology, Emory University, Atlanta, GA, USA
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4
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Patel S, Yan Z, Remedi MS. Intermittent fasting protects β-cell identity and function in a type-2 diabetes model. Metabolism 2024; 153:155813. [PMID: 38307325 PMCID: PMC10985623 DOI: 10.1016/j.metabol.2024.155813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 01/28/2024] [Accepted: 01/29/2024] [Indexed: 02/04/2024]
Abstract
Type 2 diabetes (T2DM) is caused by the interaction of multiple genes and environmental factors. T2DM is characterized by hyperglycemia, insulin secretion deficiency and insulin resistance. Chronic hyperglycemia induces β-cell dysfunction, loss of β-cell mass/identity and β-cell dedifferentiation. Intermittent fasting (IF) a commonly used dietary regimen for weight-loss, also induces metabolic benefits including reduced blood glucose, improved insulin sensitivity, reduced adiposity, inflammation, oxidative-stress and increased fatty-acid oxidation; however, the mechanisms underlying these effects in pancreatic β-cells remain elusive. KK and KKAy, mouse models of polygenic T2DM spontaneously develop hyperglycemia, glucose intolerance, glucosuria, impaired insulin secretion and insulin resistance. To determine the long-term effects of IF on T2DM, 6-weeks old KK and KKAy mice were subjected to IF for 16 weeks. While KKAy mice fed ad-libitum demonstrated severe hyperglycemia (460 mg/dL) at 6 weeks of age, KK mice showed blood glucose levels of 230 mg/dL, but progressively became severely diabetic by 22-weeks. Strikingly, both KK and KKAy mice subjected to IF showed reduced blood glucose and plasma insulin levels, decreased body weight gain, reduced plasma triglycerides and cholesterol, and improved insulin sensitivity. They also demonstrated enhanced expression of the β-cell transcription factors NKX6.1, MAFA and PDX1, and decreased expression of ALDH1a3 suggesting protection from loss of β-cell identity by IF. IF normalized glucose stimulated insulin secretion in islets from KK and KKAy mice, demonstrating improved β-cell function. In addition, hepatic steatosis, gluconeogenesis and inflammation was decreased particularly in KKAy-IF mice, indicating peripheral benefits of IF. These results have important implications as an optional intervention for preservation of β-cell identity and function in T2DM.
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Affiliation(s)
- Sumit Patel
- Department of Medicine, Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, 660 South Euclid Avenue, Saint Louis, MO, United States of America
| | - Zihan Yan
- Department of Medicine, Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, 660 South Euclid Avenue, Saint Louis, MO, United States of America
| | - Maria S Remedi
- Department of Medicine, Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, 660 South Euclid Avenue, Saint Louis, MO, United States of America; Department of Cell Biology and Physiology, Washington University School of Medicine, 660 South Euclid Avenue, Saint Louis, MO, United States of America; Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, 660 South Euclid Avenue, Saint Louis, MO, United States of America.
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5
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Sithara S, Crowley T, Walder K, Aston-Mourney K. Identification of reversible and druggable pathways to improve beta-cell function and survival in Type 2 diabetes. Islets 2023; 15:2165368. [PMID: 36709757 PMCID: PMC9888462 DOI: 10.1080/19382014.2023.2165368] [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] [Indexed: 01/30/2023] Open
Abstract
Targeting β-cell failure could prevent, delay or even partially reverse Type 2 diabetes. However, development of such drugs is limited as the molecular pathogenesis is complex and incompletely understood. Further, while β-cell failure can be modeled experimentally, only some of the molecular changes will be pathogenic. Therefore, we used a novel approach to identify molecular pathways that are not only changed in a diabetes-like state but also are reversible and can be targeted by drugs. INS1E cells were cultured in high glucose (HG, 20 mM) for 72 h or HG for an initial 24 h followed by drug addition (exendin-4, metformin and sodium salicylate) for the remaining 48 h. RNAseq (Illumina TruSeq), gene set enrichment analysis (GSEA) and pathway analysis (using Broad Institute, Reactome, KEGG and Biocarta platforms) were used to identify changes in molecular pathways. HG decreased function and increased apoptosis in INS1E cells with drugs partially reversing these effects. HG resulted in upregulation of 109 pathways while drug treatment downregulated 44 pathways with 21 pathways in common. Interestingly, while hyperglycemia extensively upregulated metabolic pathways, they were not altered with drug treatment, rather pathways involved in the cell cycle featured more heavily. GSEA for hyperglycemia identified many known pathways validating the applicability of our cell model to human disease. However, only a fraction of these pathways were downregulated with drug treatment, highlighting the importance of considering druggable pathways. Overall, this provides a powerful approach and resource for identifying appropriate targets for the development of β-cell drugs.
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Affiliation(s)
- Smithamol Sithara
- School of Medicine, IMPACT, Institute for Innovation in Physical and Mental Health and Clinical Translation, Deakin University, Geelong, Australia
| | - Tamsyn Crowley
- School of Medicine, Bioinformatics Core Research Facility, Deakin University, Geelong, Australia
| | - Ken Walder
- School of Medicine, IMPACT, Institute for Innovation in Physical and Mental Health and Clinical Translation, Deakin University, Geelong, Australia
| | - Kathryn Aston-Mourney
- School of Medicine, IMPACT, Institute for Innovation in Physical and Mental Health and Clinical Translation, Deakin University, Geelong, Australia
- CONTACT Kathryn Aston-Mourney Building Nb, 75 Pidgons Rd, Geelong, VIC3216, Australia
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Zhao G, Xu H, Li H, Zhang J, Gao J, Cai M, Wang H, Shi Y, Wang H. Regulatory Mechanisms of SNAP-25-Associated Insulin Release Revealed by Live-Cell Confocal and Single-Molecule Localization Imaging. Anal Chem 2022; 94:15307-15314. [DOI: 10.1021/acs.analchem.2c02677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Guanfang Zhao
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, P. R. China
- University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Haijiao Xu
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, P. R. China
| | - Hongru Li
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, P. R. China
- University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Jinrui Zhang
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, P. R. China
| | - Jing Gao
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, P. R. China
| | - Mingjun Cai
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, P. R. China
| | - Huili Wang
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, P. R. China
| | - Yan Shi
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, P. R. China
| | - Hongda Wang
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, P. R. China
- University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong 266237, P. R. China
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Mohan S, Lafferty RA, Flatt PR, Moffett RC, Irwin N. Ac3IV, a V1a and V1b receptor selective vasopressin analogue, protects against hydrocortisone-induced changes in pancreatic islet cell lineage. Peptides 2022; 152:170772. [PMID: 35202749 DOI: 10.1016/j.peptides.2022.170772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 02/11/2022] [Accepted: 02/17/2022] [Indexed: 11/25/2022]
Abstract
The Avpr1a (V1a) and Avpr1b (V1b) receptor selective, vasopressin (AVP) analogue, Ac3IV has been shown to improve metabolism and pancreatic islet structure in diabetes and insulin resistance. The present study further investigates these actions by assessing the ability of Ac3IV to protect against pancreatic islet architectural disturbances induced by hydrocortisone (HC) treatment in transgenic Ins1Cre/+;Rosa26-eYFP mice, that possess beta-cell lineage tracing capabilities. HC intervention increased (p < 0.001) energy intake but reduced (p < 0.01) body weight gain, with no impact of Ac3IV. All HC mice had reduced (p < 0.05) circulating glucose, but plasma insulin and glucagon concentrations remained unchanged. However, HC mice presented with increased (p < 0.001) pancreatic insulin content, which was further augmented by Ac3IV. In addition, Ac3IV treatment countered HC-induced increases in islet-, beta- and alpha-cell areas (p < 0.01), as well as promoting islet number towards control levels. This was accompanied by reduced (p < 0.05) beta-cell growth, but enhanced (p < 0.001) alpha-cell proliferation. There were no changes in islet cell apoptotic rates in any of the groups of HC mice, but co-expression of CK19 with insulin in pancreatic ductal cells was reduced by Ac3IV. Assessment of beta-cell lineage revealed that Ac3IV partially protected against HC-mediated de-differentiation of mature beta-cells, whilst also decreasing (p < 0.01) beta- to alpha-cell transdifferentiation. Our data indicate that sustained activation of V1a and V1b receptors exerts positive islet cell transition effects to help retain beta-cell identity in HC mice.
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Affiliation(s)
- Shruti Mohan
- SAAD Centre for Pharmacy and Diabetes, Ulster University, Coleraine, Northern Ireland, UK
| | - Ryan A Lafferty
- SAAD Centre for Pharmacy and Diabetes, Ulster University, Coleraine, Northern Ireland, UK
| | - Peter R Flatt
- SAAD Centre for Pharmacy and Diabetes, Ulster University, Coleraine, Northern Ireland, UK
| | - R Charlotte Moffett
- SAAD Centre for Pharmacy and Diabetes, Ulster University, Coleraine, Northern Ireland, UK
| | - Nigel Irwin
- SAAD Centre for Pharmacy and Diabetes, Ulster University, Coleraine, Northern Ireland, UK.
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Murao N, Yokoi N, Takahashi H, Hayami T, Minami Y, Seino S. Increased glycolysis affects β-cell function and identity in aging and diabetes. Mol Metab 2021; 55:101414. [PMID: 34871777 PMCID: PMC8732780 DOI: 10.1016/j.molmet.2021.101414] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 11/25/2021] [Accepted: 12/01/2021] [Indexed: 12/24/2022] Open
Abstract
Objective Age is a risk factor for type 2 diabetes (T2D). We aimed to elucidate whether β-cell glucose metabolism is altered with aging and contributes to T2D. Methods We used senescence-accelerated mice (SAM), C57BL/6J (B6) mice, and ob/ob mice as aging models. As a diabetes model, we used db/db mice. The glucose responsiveness of insulin secretion and the [U-13C]-glucose metabolic flux were examined in isolated islets. We analyzed the expression of β-cell-specific genes in isolated islets and pancreatic sections as molecular signatures of β-cell identity. β cells defective in the malate-aspartate (MA) shuttle were previously generated from MIN6-K8 cells by the knockout of Got1, a component of the shuttle. We analyzed Got1 KO β cells as a model of increased glycolysis. Results We identified hyperresponsiveness to glucose and compromised cellular identity as dysfunctional phenotypes shared in common between aged and diabetic mouse β cells. We also observed a metabolic commonality between aged and diabetic β cells: hyperactive glycolysis through the increased expression of nicotinamide mononucleotide adenylyl transferase 2 (Nmnat2), a cytosolic nicotinamide adenine dinucleotide (NAD)-synthesizing enzyme. Got1 KO β cells showed increased glycolysis, β-cell dysfunction, and impaired cellular identity, phenocopying aging and diabetes. Using Got1 KO β cells, we show that attenuation of glycolysis or Nmnat2 activity can restore β-cell function and identity. Conclusions Our study demonstrates that hyperactive glycolysis is a metabolic signature of aged and diabetic β cells, which may underlie age-related β-cell dysfunction and loss of cellular identity. We suggest Nmnat2 suppression as an approach to counteract age-related T2D. Glucose hypersensitivity and impaired identity are common features of aged and diabetic β cells. Metabolic tracing reveals increased glycolysis and altered NAD production in aged and diabetic β cells. Increased glycolysis induces β-cell dysfunction and loss of identity. NAD production by Nmnat2 can be targeted to restore β-cell phenotypes.
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Affiliation(s)
- Naoya Murao
- Division of Molecular and Metabolic Medicine, Graduate School of Medicine, Kobe University, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017, Japan
| | - Norihide Yokoi
- Division of Molecular and Metabolic Medicine, Graduate School of Medicine, Kobe University, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017, Japan; Laboratory of Animal Breeding and Genetics, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Kyoto 606-8502, Japan
| | - Harumi Takahashi
- Division of Molecular and Metabolic Medicine, Graduate School of Medicine, Kobe University, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017, Japan.
| | - Tomohide Hayami
- Division of Molecular and Metabolic Medicine, Graduate School of Medicine, Kobe University, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017, Japan; Division of Diabetes, Department of Internal Medicine, Aichi Medical University, Nagakute, Aichi 480-1195, Japan
| | - Yasuhiro Minami
- Division of Cell Physiology, Graduate School of Medicine, Kobe University, Chuo-ku, Kobe, Hyogo 650-0017, Japan
| | - Susumu Seino
- Division of Molecular and Metabolic Medicine, Graduate School of Medicine, Kobe University, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017, Japan
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Singh R, Mohapatra L, Tripathi AS. Targeting mitochondrial biogenesis: a potential approach for preventing and controlling diabetes. FUTURE JOURNAL OF PHARMACEUTICAL SCIENCES 2021. [DOI: 10.1186/s43094-021-00360-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Diabetes mellitus is a lingering hyperglycemic ailment resulting in several life-threatening difficulties. Enduring hyperglycemia often persuades the buildup of reactive oxygen species that are the significant pathological makers of diabetic complications. The mitochondrial dysfunction, with mitochondrial damage and too much production of reactive oxygen species, have been proposed to be convoluted in the progress of insulin resistance. Numerous studies advocate that agents that enhance the mitochondrial number and/or decrease their dysfunction, could be greatly helpful in management of diabetes and its complications.
Main body
Mitochondrial biogenesis is an extremely delimited procedure arbitrated by numerous transcription influences, in which mitochondrial fusion and fission happen in synchronization in a standard vigorous cell. But this synchronization is greatly disturbed in diabetic condition designated by modification in the working of several important transcription factors regulating the expressions of different genes. Numerous preclinical and clinical investigations have suggested that, the compromised functions of mitochondria play a significant protagonist in development of pancreatic β-cell dysfunction, skeletal muscle insulin resistance and several diabetic complications. However, there are several phytoconstituents performing through numerous alleyways, either unswervingly by motivating biogenesis or indirectly by constraining or averting dysfunction and producing a beneficial effect on overall function of the mitochondria.
Conclusion
This review describes standard mitochondrial physiology and anomalous modifications that transpire in answer to persistent hyperglycemia in diabetes condition. It also discusses about the different phytoconstituents that can affect the biogenesis pathways of mitochondria and thus can be used in the treatment and prevention of diabetes.
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10
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Brown MR, Holmes H, Rakshit K, Javeed N, Her TK, Stiller AA, Sen S, Shull GE, Prakash YS, Romero MF, Matveyenko AV. Electrogenic sodium bicarbonate cotransporter NBCe1 regulates pancreatic β cell function in type 2 diabetes. J Clin Invest 2021; 131:142365. [PMID: 34623331 DOI: 10.1172/jci142365] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 07/22/2021] [Indexed: 12/13/2022] Open
Abstract
Pancreatic β cell failure in type 2 diabetes mellitus (T2DM) is attributed to perturbations of the β cell's transcriptional landscape resulting in impaired glucose-stimulated insulin secretion. Recent studies identified SLC4A4 (a gene encoding an electrogenic Na+-coupled HCO3- cotransporter and intracellular pH regulator, NBCe1) as one of the misexpressed genes in β cells of patients with T2DM. Thus, in the current study, we set out to test the hypothesis that misexpression of SLC4A4/NBCe1 in T2DM β cells contributes to β cell dysfunction and impaired glucose homeostasis. To address this hypothesis, we first confirmed induction of SLC4A4/NBCe1 expression in β cells of patients with T2DM and demonstrated that its expression was associated with loss of β cell transcriptional identity, intracellular alkalinization, and β cell dysfunction. In addition, we generated a β cell-selective Slc4a4/NBCe1-KO mouse model and found that these mice were protected from diet-induced metabolic stress and β cell dysfunction. Importantly, improved glucose tolerance and enhanced β cell function in Slc4a4/NBCe1-deficient mice were due to augmented mitochondrial function and increased expression of genes regulating β cell identity and function. These results suggest that increased β cell expression of SLC4A4/NBCe1 in T2DM plays a contributory role in promotion of β cell failure and should be considered as a potential therapeutic target.
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Affiliation(s)
- Matthew R Brown
- Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine and Science, Rochester, Minnesota, USA
| | - Heather Holmes
- Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine and Science, Rochester, Minnesota, USA
| | - Kuntol Rakshit
- Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine and Science, Rochester, Minnesota, USA
| | - Naureen Javeed
- Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine and Science, Rochester, Minnesota, USA
| | - Tracy K Her
- Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine and Science, Rochester, Minnesota, USA
| | - Alison A Stiller
- Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine and Science, Rochester, Minnesota, USA
| | - Satish Sen
- Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine and Science, Rochester, Minnesota, USA
| | - Gary E Shull
- Department of Molecular Genetics, Biochemistry, and Microbiology, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Y S Prakash
- Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine and Science, Rochester, Minnesota, USA.,Department of Anesthesiology
| | - Michael F Romero
- Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine and Science, Rochester, Minnesota, USA.,Division of Nephrology and Hypertension and
| | - Aleksey V Matveyenko
- Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine and Science, Rochester, Minnesota, USA.,Division of Endocrinology, Metabolism, Diabetes, and Nutrition, Department of Medicine, Mayo Clinic College of Medicine and Science, Rochester, Minnesota, USA
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Sanchez PKM, Khazaei M, Gatineau E, Geravandi S, Lupse B, Liu H, Dringen R, Wojtusciszyn A, Gilon P, Maedler K, Ardestani A. LDHA is enriched in human islet alpha cells and upregulated in type 2 diabetes. Biochem Biophys Res Commun 2021; 568:158-166. [PMID: 34217973 DOI: 10.1016/j.bbrc.2021.06.065] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 06/20/2021] [Indexed: 12/25/2022]
Abstract
The lactate dehydrogenase isoform A (LDHA) is a key metabolic enzyme that preferentially catalyzes the conversion of pyruvate to lactate. Whereas LDHA is highly expressed in many tissues, its expression is turned off in the differentiated adult β-cell within the pancreatic islets. The repression of LDHA under normal physiological condition and its inappropriate upregulation under a diabetogenic environment is well-documented in rodent islets/β-cells but little is known about LDHA expression in human islet cells and whether its abundance is altered under diabetic conditions. Analysis of public single-cell RNA-seq (sc-RNA seq) data as well as cell type-specific immunolabeling of human pancreatic islets showed that LDHA was mainly localized in human α-cells while it is expressed at a very low level in β-cells. Furthermore, LDHA, both at mRNA and protein, as well as lactate production is upregulated in human pancreatic islets exposed to chronic high glucose treatment. Microscopic analysis of stressed human islets and autopsy pancreases from individuals with type 2 diabetes (T2D) showed LDHA upregulation mainly in human α-cells. Pharmacological inhibition of LDHA in isolated human islets enhanced insulin secretion under physiological conditions but did not significantly correct the deregulated secretion of insulin or glucagon under diabetic conditions.
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Affiliation(s)
| | - Mona Khazaei
- Centre for Biomolecular Interactions Bremen, University of Bremen, Bremen, Germany
| | - Eva Gatineau
- Pole of Endocrinology, Diabetes, and Nutrition (EDIN), Institute of Experimental and Clinical Research (IREC), Université Catholique de Louvain (UCLouvain), 1200, Brussels, Belgium
| | - Shirin Geravandi
- Centre for Biomolecular Interactions Bremen, University of Bremen, Bremen, Germany
| | - Blaz Lupse
- Centre for Biomolecular Interactions Bremen, University of Bremen, Bremen, Germany
| | - Huan Liu
- Centre for Biomolecular Interactions Bremen, University of Bremen, Bremen, Germany
| | - Ralf Dringen
- Centre for Biomolecular Interactions Bremen, University of Bremen, Bremen, Germany
| | - Anne Wojtusciszyn
- Department of Endocrinology, Diabetology and Metabolism, Lausanne University Hospital, Lausanne, Switzerland
| | - Patrick Gilon
- Pole of Endocrinology, Diabetes, and Nutrition (EDIN), Institute of Experimental and Clinical Research (IREC), Université Catholique de Louvain (UCLouvain), 1200, Brussels, Belgium
| | - Kathrin Maedler
- Centre for Biomolecular Interactions Bremen, University of Bremen, Bremen, Germany.
| | - Amin Ardestani
- Centre for Biomolecular Interactions Bremen, University of Bremen, Bremen, Germany; Department of Molecular Medicine, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran.
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12
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Miranda MA, Macias-Velasco JF, Lawson HA. Pancreatic β-cell heterogeneity in health and diabetes: classes, sources, and subtypes. Am J Physiol Endocrinol Metab 2021; 320:E716-E731. [PMID: 33586491 PMCID: PMC8238131 DOI: 10.1152/ajpendo.00649.2020] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Pancreatic β-cells perform glucose-stimulated insulin secretion, a process at the center of type 2 diabetes etiology. Efforts to understand how β-cells behave in healthy and stressful conditions have revealed a wide degree of morphological, functional, and transcriptional heterogeneity. Sources of heterogeneity include β-cell topography, developmental origin, maturation state, and stress response. Advances in sequencing and imaging technologies have led to the identification of β-cell subtypes, which play distinct roles in the islet niche. This review examines β-cell heterogeneity from morphological, functional, and transcriptional perspectives, and considers the relevance of topography, maturation, development, and stress response. It also discusses how these factors have been used to identify β-cell subtypes, and how heterogeneity is impacted by diabetes. We examine open questions in the field and discuss recent technological innovations that could advance understanding of β-cell heterogeneity in health and disease.
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Affiliation(s)
- Mario A Miranda
- Department of Genetics, Washington University School of Medicine, Saint Louis, Missouri
| | - Juan F Macias-Velasco
- Department of Genetics, Washington University School of Medicine, Saint Louis, Missouri
| | - Heather A Lawson
- Department of Genetics, Washington University School of Medicine, Saint Louis, Missouri
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13
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Spears E, Serafimidis I, Powers AC, Gavalas A. Debates in Pancreatic Beta Cell Biology: Proliferation Versus Progenitor Differentiation and Transdifferentiation in Restoring β Cell Mass. Front Endocrinol (Lausanne) 2021; 12:722250. [PMID: 34421829 PMCID: PMC8378310 DOI: 10.3389/fendo.2021.722250] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 07/14/2021] [Indexed: 12/12/2022] Open
Abstract
In all forms of diabetes, β cell mass or function is reduced and therefore the capacity of the pancreatic cells for regeneration or replenishment is a critical need. Diverse lines of research have shown the capacity of endocrine as well as acinar, ductal and centroacinar cells to generate new β cells. Several experimental approaches using injury models, pharmacological or genetic interventions, isolation and in vitro expansion of putative progenitors followed by transplantations or a combination thereof have suggested several pathways for β cell neogenesis or regeneration. The experimental results have also generated controversy related to the limitations and interpretation of the experimental approaches and ultimately their physiological relevance, particularly when considering differences between mouse, the primary animal model, and human. As a result, consensus is lacking regarding the relative importance of islet cell proliferation or progenitor differentiation and transdifferentiation of other pancreatic cell types in generating new β cells. In this review we summarize and evaluate recent experimental approaches and findings related to islet regeneration and address their relevance and potential clinical application in the fight against diabetes.
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Affiliation(s)
- Erick Spears
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Ioannis Serafimidis
- Center of Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | - Alvin C. Powers
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, United States
- VA Tennessee Valley Healthcare System, Nashville, TN, United States
- *Correspondence: Anthony Gavalas, ; Alvin C. Powers,
| | - Anthony Gavalas
- Paul Langerhans Institute Dresden (PLID) of Helmholtz Center Munich at the University Clinic Carl Gustav Carus of TU Dresden, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- German Centre for Diabetes Research (DZD), Neuherberg, Germany
- *Correspondence: Anthony Gavalas, ; Alvin C. Powers,
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14
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Liu J, Lang G, Shi J. Epigenetic Regulation of PDX-1 in Type 2 Diabetes Mellitus. Diabetes Metab Syndr Obes 2021; 14:431-442. [PMID: 33564250 PMCID: PMC7866918 DOI: 10.2147/dmso.s291932] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 01/16/2021] [Indexed: 12/25/2022] Open
Abstract
Type 2 diabetes mellitus (T2DM) is a metabolic disease characterized by hyperglycemia which is caused by insufficient insulin secretion or insulin resistance. Interaction of genetic, epigenetic and environmental factors plays a significant role in the development of T2DM. Several environmental factors including diet and lifestyle, as well as age have been associated with an increased risk for T2DM. It has been demonstrated that these environmental factors may affect global epigenetic status, and alter the expression of susceptible genes, thereby contributing to the pathogenesis of T2DM. In recent years, a growing body of molecular and genetic studies in diabetes have been focused on the ways to restore the numbers or function of β-cells in order to reverse a range of metabolic consequences of insulin deficiency. The pancreatic duodenal homeobox 1 (PDX-1) is a transcriptional factor that is essential for the development and function of islet cells. A number of studies have shown that there is a significant increase in the level of DNA methylation of PDX-1 resulting in reduced activity in T2DM islets. The decrease in PDX-1 activity may be a critical mediator causing dysregulation of pancreatic β cells in T2DM. This article reviews the epigenetic mechanisms of PDX-1 involved in T2DM, focusing on diabetes and DNA methylation, and discusses some potential strategies for the application of PDX-1 in the treatment of diabetes.
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Affiliation(s)
- Jiangman Liu
- Key Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, Zunyi Medical University, Zunyi, 563000, People’s Republic of China
| | - Guangping Lang
- Key Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, Zunyi Medical University, Zunyi, 563000, People’s Republic of China
| | - Jingshan Shi
- Key Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, Zunyi Medical University, Zunyi, 563000, People’s Republic of China
- Correspondence: Jingshan Shi Tel +86-851-286-436-66Fax +86-851-286-423-03 Email
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15
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Bilekova S, Sachs S, Lickert H. Pharmacological Targeting of Endoplasmic Reticulum Stress in Pancreatic Beta Cells. Trends Pharmacol Sci 2020; 42:85-95. [PMID: 33353789 DOI: 10.1016/j.tips.2020.11.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 11/20/2020] [Accepted: 11/24/2020] [Indexed: 02/06/2023]
Abstract
Diabetes is a disease with pandemic dimensions and no pharmacological treatment prevents disease progression. Dedifferentiation has been proposed to be a driver of beta-cell dysfunction in both type 1 and type 2 diabetes. Regenerative therapies aim to re-establish function in dysfunctional or dedifferentiated beta cells and restore the defective insulin secretion. Unsustainable levels of insulin production, with increased demand at disease onset, strain the beta-cell secretory machinery, leading to endoplasmic reticulum (ER) stress. Unresolved chronic ER stress is a major contributor to beta-cell loss of function and identity. Restoring ER homeostasis, enhancing ER-associated degradation of misfolded protein, and boosting chaperoning activity, are emerging therapeutic approaches for diabetes treatment.
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Affiliation(s)
- Sara Bilekova
- Institute of Diabetes and Regeneration Research, Helmholtz Zentrum München, Neuherberg, Germany; German Center for Diabetes Research (DZD), Neuherberg, Germany; Technical University of Munich, Medical Faculty, Munich, Germany
| | - Stephan Sachs
- Institute of Diabetes and Regeneration Research, Helmholtz Zentrum München, Neuherberg, Germany; German Center for Diabetes Research (DZD), Neuherberg, Germany; Technical University of Munich, Medical Faculty, Munich, Germany
| | - Heiko Lickert
- Institute of Diabetes and Regeneration Research, Helmholtz Zentrum München, Neuherberg, Germany; German Center for Diabetes Research (DZD), Neuherberg, Germany; Technical University of Munich, Medical Faculty, Munich, Germany; Institute of Stem Cell Research, Helmholtz Zentrum München, Neuherberg, Germany.
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16
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Rattanaporn P, Tongsima S, Mandrup-Poulsen T, Svasti S, Tanyong D. Combination of ferric ammonium citrate with cytokines involved in apoptosis and insulin secretion of human pancreatic beta cells related to diabetes in thalassemia. PeerJ 2020; 8:e9298. [PMID: 32587797 PMCID: PMC7304432 DOI: 10.7717/peerj.9298] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 05/14/2020] [Indexed: 01/09/2023] Open
Abstract
Background Diabetes mellitus (DM) is a common complication found in β-thalassemia patients. The mechanism of DM in β-thalassemia patients is still unclear, but it could be from an iron overload and increase of some cytokines, such as interleukin1-β (IL-1β) and tumor necrosis factor-α (TNF-α). The objective of this study was to study the effect of interaction between ferric ammonium citrate (FAC) and cytokines, IL-1β and TNF-α, on 1.1B4 human pancreatic β-cell line. Methods The effect of the combination of FAC and cytokines on cell viability was studied by MTT assay. Insulin secretion was assessed by the enzyme-linked immunosorbent assay (ELISA). The reactive oxygen species (ROS) and cell apoptosis in normal and high glucose condition were determined by flow cytometer. In addition, gene expression of apoptosis, antioxidant; glutathione peroxidase 1 (GPX1) and superoxide dismutase 2 (SOD2), and insulin secretory function were studied by real-time polymerase chain reaction (Real-time PCR). Results The findings revealed that FAC exposure resulted in the decrease of cell viability and insulin-release, and the induction of ROS and apoptosis in pancreatic cells. Interestingly, a combination of FAC and cytokines had an additive effect on SOD2 antioxidants' genes expression and endoplasmic reticulum (ER) stress. In addition, it reduced the insulin secretion genes expression; insulin (INS), glucose kinase (GCK), protein convertase 1 (PSCK1), and protein convertase 2 (PSCK2). Moreover, the highest ROS and the lowest insulin secretion were found in FAC combined with IL-1β and TNF-α in the high-glucose condition of human pancreatic beta cell, which could be involved in the mechanism of DM development in β-thalassemia patients.
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Affiliation(s)
- Patchara Rattanaporn
- Department of Clinical Microscopic, Faculty of Medical Technology, Mahidol University, Nakhon Pathom, Thailand.,Thalassemia Research Center, Institute of Molecular Biosciences, Mahidol University, Nakhon Pathom, Thailand
| | - Sissades Tongsima
- National Biobank of Thailand, National Science and Technology Development Agency, Pathum Thani, Thailand.,National Center for Genetics Engineering and Biotechnology, National Science and Technology Development Agency, Pathum Thani, Thailand
| | - Thomas Mandrup-Poulsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Saovaros Svasti
- Thalassemia Research Center, Institute of Molecular Biosciences, Mahidol University, Nakhon Pathom, Thailand.,Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Dalina Tanyong
- Department of Clinical Microscopic, Faculty of Medical Technology, Mahidol University, Nakhon Pathom, Thailand
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17
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Ebrahimi AG, Hollister-Lock J, Sullivan BA, Tsuchida R, Bonner-Weir S, Weir GC. Beta cell identity changes with mild hyperglycemia: Implications for function, growth, and vulnerability. Mol Metab 2020; 35:100959. [PMID: 32244186 PMCID: PMC7082551 DOI: 10.1016/j.molmet.2020.02.002] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 02/03/2020] [Accepted: 02/04/2020] [Indexed: 02/08/2023] Open
Abstract
OBJECTIVE As diabetes develops, marked reductions of insulin secretion are associated with very modest elevations of glucose. We wondered if these glucose changes disrupt beta cell differentiation enough to account for the altered function. METHODS Rats were subjected to 90% partial pancreatectomies and those with only mild glucose elevations 4 weeks or 10 weeks after surgery had major alterations of gene expression in their islets as determined by RNAseq. RESULTS Changes associated with glucose toxicity demonstrated that many of the critical genes responsible for insulin secretion were downregulated while the expression of normally suppressed genes increased. Also, there were marked changes in genes associated with replication, aging, senescence, stress, inflammation, and increased expression of genes controlling both class I and II MHC antigens. CONCLUSIONS These findings suggest that mild glucose elevations in the early stages of diabetes lead to phenotypic changes that adversely affect beta cell function, growth, and vulnerability.
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Affiliation(s)
- Aref G Ebrahimi
- Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, One Joslin Place, Harvard Medical School, Boston, MA 02215, USA
| | - Jennifer Hollister-Lock
- Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, One Joslin Place, Harvard Medical School, Boston, MA 02215, USA
| | - Brooke A Sullivan
- Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, One Joslin Place, Harvard Medical School, Boston, MA 02215, USA
| | - Ryohei Tsuchida
- Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, One Joslin Place, Harvard Medical School, Boston, MA 02215, USA
| | - Susan Bonner-Weir
- Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, One Joslin Place, Harvard Medical School, Boston, MA 02215, USA
| | - Gordon C Weir
- Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, One Joslin Place, Harvard Medical School, Boston, MA 02215, USA.
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18
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Fan J, Du W, Kim-Muller JY, Son J, Kuo T, Larrea D, Garcia C, Kitamoto T, Kraakman MJ, Owusu-Ansah E, Cirulli V, Accili D. Cyb5r3 links FoxO1-dependent mitochondrial dysfunction with β-cell failure. Mol Metab 2020; 34:97-111. [PMID: 32180563 PMCID: PMC7031142 DOI: 10.1016/j.molmet.2019.12.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 12/03/2019] [Accepted: 12/12/2019] [Indexed: 12/25/2022] Open
Abstract
OBJECTIVE Diabetes is characterized by pancreatic β-cell dedifferentiation. Dedifferentiating β cells inappropriately metabolize lipids over carbohydrates and exhibit impaired mitochondrial oxidative phosphorylation. However, the mechanism linking the β-cell's response to an adverse metabolic environment with impaired mitochondrial function remains unclear. METHODS Here we report that the oxidoreductase cytochrome b5 reductase 3 (Cyb5r3) links FoxO1 signaling to β-cell stimulus/secretion coupling by regulating mitochondrial function, reactive oxygen species generation, and nicotinamide actin dysfunction (NAD)/reduced nicotinamide actin dysfunction (NADH) ratios. RESULTS The expression of Cyb5r3 is decreased in FoxO1-deficient β cells. Mice with β-cell-specific deletion of Cyb5r3 have impaired insulin secretion, resulting in glucose intolerance and diet-induced hyperglycemia. Cyb5r3-deficient β cells have a blunted respiratory response to glucose and display extensive mitochondrial and secretory granule abnormalities, consistent with altered differentiation. Moreover, FoxO1 is unable to maintain expression of key differentiation markers in Cyb5r3-deficient β cells, suggesting that Cyb5r3 is required for FoxO1-dependent lineage stability. CONCLUSIONS The findings highlight a pathway linking FoxO1 to mitochondrial dysfunction that can mediate β-cell failure.
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Affiliation(s)
- Jason Fan
- Naomi Berrie Diabetes Center and Departments of Medicine, Columbia University, New York, NY 10032, USA
| | - Wen Du
- Naomi Berrie Diabetes Center and Departments of Medicine, Columbia University, New York, NY 10032, USA
| | - Ja Young Kim-Muller
- Naomi Berrie Diabetes Center and Departments of Medicine, Columbia University, New York, NY 10032, USA
| | - Jinsook Son
- Naomi Berrie Diabetes Center and Departments of Medicine, Columbia University, New York, NY 10032, USA
| | - Taiyi Kuo
- Naomi Berrie Diabetes Center and Departments of Medicine, Columbia University, New York, NY 10032, USA
| | - Delfina Larrea
- Department of Neurology, Columbia University, New York, NY 10032, USA
| | - Christian Garcia
- Physiology and Cellular Biophysics, Columbia University, New York, NY 10032, USA
| | - Takumi Kitamoto
- Naomi Berrie Diabetes Center and Departments of Medicine, Columbia University, New York, NY 10032, USA
| | - Michael J Kraakman
- Naomi Berrie Diabetes Center and Departments of Medicine, Columbia University, New York, NY 10032, USA
| | - Edward Owusu-Ansah
- Physiology and Cellular Biophysics, Columbia University, New York, NY 10032, USA
| | - Vincenzo Cirulli
- Department of Medicine, UW-Diabetes Institute, Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA, USA
| | - Domenico Accili
- Naomi Berrie Diabetes Center and Departments of Medicine, Columbia University, New York, NY 10032, USA.
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19
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Weir GC. Glucolipotoxicity, β-Cells, and Diabetes: The Emperor Has No Clothes. Diabetes 2020; 69:273-278. [PMID: 31519699 PMCID: PMC7034184 DOI: 10.2337/db19-0138] [Citation(s) in RCA: 96] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 04/08/2019] [Indexed: 12/21/2022]
Abstract
Reduction of β-cell mass and function is central to the pathogenesis of type 2 diabetes. The terms glucotoxicity, lipotoxicity, and glucolipotoxicity are used to describe potentially responsible processes. The premise is that chronically elevated glucose levels are toxic to β-cells, that elevated lipid levels in the form of circulating free fatty acids (FFA) also have toxic effects, and that the combination of the two, glucolipotoxicity, is particularly harmful. Much work has shown that high concentrations of FFA can be very damaging to β-cells when used for in vitro experiments, and when infused in large amounts in humans and rodents they produce suppression of insulin secretion. The purpose of this Perspective is to raise doubts about whether the FFA levels found in real-life situations are ever high enough to cause problems. Evidence supporting the importance of glucotoxicity is strong because there is such a tight correlation between defective insulin secretion and rising glucose levels. However, there is virtually no convincing evidence that the alterations in FFA levels occurring during progression to diabetes are pathogenic. Thus, the terms lipotoxicity and glucolipotoxicity should be used with great caution, if at all, because evidence supporting their importance has not yet emerged.
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Affiliation(s)
- Gordon C Weir
- Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, Harvard Medical School, Boston, MA
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20
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Salinno C, Cota P, Bastidas-Ponce A, Tarquis-Medina M, Lickert H, Bakhti M. β-Cell Maturation and Identity in Health and Disease. Int J Mol Sci 2019; 20:E5417. [PMID: 31671683 PMCID: PMC6861993 DOI: 10.3390/ijms20215417] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 10/28/2019] [Accepted: 10/28/2019] [Indexed: 12/15/2022] Open
Abstract
The exponential increase of patients with diabetes mellitus urges for novel therapeutic strategies to reduce the socioeconomic burden of this disease. The loss or dysfunction of insulin-producing β-cells, in patients with type 1 and type 2 diabetes respectively, put these cells at the center of the disease initiation and progression. Therefore, major efforts have been taken to restore the β-cell mass by cell-replacement or regeneration approaches. Implementing novel therapies requires deciphering the developmental mechanisms that generate β-cells and determine the acquisition of their physiological phenotype. In this review, we summarize the current understanding of the mechanisms that coordinate the postnatal maturation of β-cells and define their functional identity. Furthermore, we discuss different routes by which β-cells lose their features and functionality in type 1 and 2 diabetic conditions. We then focus on potential mechanisms to restore the functionality of those β-cell populations that have lost their functional phenotype. Finally, we discuss the recent progress and remaining challenges facing the generation of functional mature β-cells from stem cells for cell-replacement therapy for diabetes treatment.
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Affiliation(s)
- Ciro Salinno
- Institute of Diabetes and Regeneration Research, Helmholtz Zentrum München, D-85764 Neuherberg, Germany.
- German Center for Diabetes Research (DZD), D-85764 Neuherberg, Germany.
- Institute of Stem Cell Research, Helmholtz Zentrum München, D-85764 Neuherberg, Germany.
- School of Medicine, Technical University of Munich, 81675Munich, Germany.
| | - Perla Cota
- Institute of Diabetes and Regeneration Research, Helmholtz Zentrum München, D-85764 Neuherberg, Germany.
- German Center for Diabetes Research (DZD), D-85764 Neuherberg, Germany.
- Institute of Stem Cell Research, Helmholtz Zentrum München, D-85764 Neuherberg, Germany.
- School of Medicine, Technical University of Munich, 81675Munich, Germany.
| | - Aimée Bastidas-Ponce
- Institute of Diabetes and Regeneration Research, Helmholtz Zentrum München, D-85764 Neuherberg, Germany.
- German Center for Diabetes Research (DZD), D-85764 Neuherberg, Germany.
- Institute of Stem Cell Research, Helmholtz Zentrum München, D-85764 Neuherberg, Germany.
- School of Medicine, Technical University of Munich, 81675Munich, Germany.
| | - Marta Tarquis-Medina
- Institute of Diabetes and Regeneration Research, Helmholtz Zentrum München, D-85764 Neuherberg, Germany.
- German Center for Diabetes Research (DZD), D-85764 Neuherberg, Germany.
- Institute of Stem Cell Research, Helmholtz Zentrum München, D-85764 Neuherberg, Germany.
- School of Medicine, Technical University of Munich, 81675Munich, Germany.
| | - Heiko Lickert
- Institute of Diabetes and Regeneration Research, Helmholtz Zentrum München, D-85764 Neuherberg, Germany.
- German Center for Diabetes Research (DZD), D-85764 Neuherberg, Germany.
- Institute of Stem Cell Research, Helmholtz Zentrum München, D-85764 Neuherberg, Germany.
- School of Medicine, Technical University of Munich, 81675Munich, Germany.
| | - Mostafa Bakhti
- Institute of Diabetes and Regeneration Research, Helmholtz Zentrum München, D-85764 Neuherberg, Germany.
- German Center for Diabetes Research (DZD), D-85764 Neuherberg, Germany.
- Institute of Stem Cell Research, Helmholtz Zentrum München, D-85764 Neuherberg, Germany.
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21
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Tirinato L, Pagliari F, Di Franco S, Sogne E, Marafioti MG, Jansen J, Falqui A, Todaro M, Candeloro P, Liberale C, Seco J, Stassi G, Di Fabrizio E. ROS and Lipid Droplet accumulation induced by high glucose exposure in healthy colon and Colorectal Cancer Stem Cells. Genes Dis 2019; 7:620-635. [PMID: 33335962 PMCID: PMC7729111 DOI: 10.1016/j.gendis.2019.09.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 09/12/2019] [Indexed: 12/17/2022] Open
Abstract
Lipid Droplets (LDs) are emerging as crucial players in colon cancer development and maintenance. Their expression has been associated with high tumorigenicity in Cancer Stem Cells (CSCs), so that they have been proposed as a new functional marker in Colorectal Cancer Stem Cells (CR-CSCs). They are also indirectly involved in the modulation of the tumor microenvironment through the production of pro-inflammatory molecules. There is growing evidence that a possible connection between metabolic alterations and malignant transformation exists, although the effects of nutrients, primarily glucose, on the CSC behavior are still mostly unexplored. Glucose is an essential fuel for cancer cells, and the connections with LDs in the healthy and CSC populations merit to be more deeply investigated. Here, we showed that a high glucose concentration activated the PI3K/AKT pathway and increased the expression of CD133 and CD44v6 CSC markers. Additionally, glucose was responsible for the increased amount of Reactive Oxygen Species (ROS) and LDs in both healthy and CR-CSC samples. We also investigated the gene modulations following the HG treatment and found out that the healthy cell gene profile was the most affected. Lastly, Atorvastatin, a lipid-lowering drug, induced the highest mortality on CR-CSCs without affecting the healthy counterpart.
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Affiliation(s)
- Luca Tirinato
- Biomedical Physics in Radiation Oncology, DKFZ (German Cancer Research Center), 69120 Heidelberg, Germany.,Physical Science and Engineering (PSE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia.,Department of Experimental and Clinical Medicine, University "Magna Graecia" of Catanzaro, 88100 Loc. Germaneto, Catanzaro, Italy
| | - Francesca Pagliari
- Biomedical Physics in Radiation Oncology, DKFZ (German Cancer Research Center), 69120 Heidelberg, Germany.,Biological and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Simone Di Franco
- Cellular and Molecular Pathophysiology Laboratory, Department of Surgical, Oncological and Stomatological Sciences, University of Palermo, Palermo, Italy
| | - Elisa Sogne
- Biological and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Maria Grazia Marafioti
- Biomedical Physics in Radiation Oncology, DKFZ (German Cancer Research Center), 69120 Heidelberg, Germany
| | - Jeanette Jansen
- Biomedical Physics in Radiation Oncology, DKFZ (German Cancer Research Center), 69120 Heidelberg, Germany.,Ruprecht Karls University Heidelberg, Department of Physics, 69120 Heidelberg, Germany
| | - Andrea Falqui
- Biological and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Matilde Todaro
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties (PROMISE), University of Palermo, Palermo, Italy
| | - Patrizio Candeloro
- Department of Experimental and Clinical Medicine, University "Magna Graecia" of Catanzaro, 88100 Loc. Germaneto, Catanzaro, Italy
| | - Carlo Liberale
- Biological and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Joao Seco
- Biomedical Physics in Radiation Oncology, DKFZ (German Cancer Research Center), 69120 Heidelberg, Germany.,Ruprecht Karls University Heidelberg, Department of Physics, 69120 Heidelberg, Germany
| | - Giorgio Stassi
- Cellular and Molecular Pathophysiology Laboratory, Department of Surgical, Oncological and Stomatological Sciences, University of Palermo, Palermo, Italy
| | - Enzo Di Fabrizio
- Physical Science and Engineering (PSE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
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22
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Da Silva Xavier G, Rutter GA. Metabolic and Functional Heterogeneity in Pancreatic β Cells. J Mol Biol 2019; 432:1395-1406. [PMID: 31419404 DOI: 10.1016/j.jmb.2019.08.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 07/17/2019] [Accepted: 08/05/2019] [Indexed: 01/01/2023]
Abstract
Metabolic and secretory heterogeneity are fundamental properties of pancreatic islet β cells. Emerging data suggest that stable differences in the transcriptome and proteome of individual cells may create cellular hierarchies, which, in turn, establish coordinated functional networks. These networks appear to govern the secretory activity of the whole islet and be affected in some forms of diabetes mellitus. Functional imaging, for example, of intracellular calcium dynamics, has led to the demonstration of "small worlds" behavior, and the identification of highly connected "hub" (or "leader") cells and of follower populations subservient to them. Subsequent inactivation of members of either population, for example, using optogenetic approaches or photoablation, has confirmed the importance of hub cells as possible pacemakers. Hub cells appear to be enriched for the glucose phosphorylating enzyme glucokinase and for genes encoding other enzymes involved in glucose metabolism compared to follower cells. Recent findings have shown the relevance of cellular hierarchy in islets from multiple species including human, mouse and fish, and shown that it is preserved in vivo in the context of the fully vascularized and innervated islet. Importantly, connectivity is impaired by insults, which mimic the diabetic milieu, including high glucose and/or fatty levels, and by the ablation of genes associated with type 2 diabetes risk in genome-wide association studies. We discuss here the evidence for the existence of these networks and their failure in disease settings. We also briefly survey the challenges in understanding their properties.
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Affiliation(s)
- Gabriela Da Silva Xavier
- Institute of Metabolism and Systems Research (IMSR), University of Birmingham, Edgbaston, United Kingdom.
| | - Guy A Rutter
- Section of Cell Biology and Functional Genomics, Department of Medicine, Imperial College London, Hammersmith Hospital, Du Cane Road, London, W12 0NN, United Kingdom; Lee Kong Chian School of Medicine, Nan Yang Technological University, Singapore
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23
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Westermeier F, Holyoak T, Asenjo JL, Gatica R, Nualart F, Burbulis I, Bertinat R. Gluconeogenic Enzymes in β-Cells: Pharmacological Targets for Improving Insulin Secretion. Trends Endocrinol Metab 2019; 30:520-531. [PMID: 31213347 DOI: 10.1016/j.tem.2019.05.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 05/14/2019] [Accepted: 05/16/2019] [Indexed: 02/06/2023]
Abstract
Pancreatic β-cells express the gluconeogenic enzymes glucose 6-phosphatase (G6Pase), fructose 1,6-bisphosphatase (FBP), and phosphoenolpyruvate (PEP) carboxykinase (PCK), which modulate glucose-stimulated insulin secretion (GSIS) through their ability to reverse otherwise irreversible glycolytic steps. Here, we review current knowledge about the expression and regulation of these enzymes in the context of manipulating them to improve insulin secretion in diabetics. Because the regulation of gluconeogenic enzymes in β-cells is so poorly understood, we propose novel research avenues to study these enzymes as modulators of insulin secretion and β-cell dysfunction, with especial attention to FBP, which constitutes an attractive target with an inhibitor under clinical evaluation at present.
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Affiliation(s)
- Francisco Westermeier
- FH JOANNEUM Gesellschaft mbH University of Applied Sciences, Institute of Biomedical Science, Eggenberger Allee 13, 8020 Graz, Austria
| | - Todd Holyoak
- Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Joel L Asenjo
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, Independencia 631, 5110566 Valdivia, Chile
| | - Rodrigo Gatica
- Escuela de Veterinaria, Facultad de Ciencias, Universidad Mayor, La Pirámide 5750, 8580745 Santiago, Chile
| | - Francisco Nualart
- Centro de Microscopía Avanzada, CMA BIO, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160 C, 4030000 Concepción, Chile
| | - Ian Burbulis
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Virginia, Jordan Hall Room 6022, 1340 Jefferson Park Avenue, Charlottesville, VA 22908, USA; Escuela de Medicina, Universidad San Sebastián, Sede Patagonia, Lago Panguipulli 1390, 5501842 Puerto Montt, Chile
| | - Romina Bertinat
- Centro de Microscopía Avanzada, CMA BIO, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160 C, 4030000 Concepción, Chile.
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24
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Elmasry K, Ibrahim AS, Abdulmoneim S, Al-Shabrawey M. Bioactive lipids and pathological retinal angiogenesis. Br J Pharmacol 2019; 176:93-109. [PMID: 30276789 PMCID: PMC6284336 DOI: 10.1111/bph.14507] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 08/14/2018] [Accepted: 08/22/2018] [Indexed: 12/22/2022] Open
Abstract
Angiogenesis, disruption of the retinal barrier, leukocyte-adhesion and oedema are cardinal signs of proliferative retinopathies that are associated with vision loss. Therefore, identifying factors that regulate these vascular dysfunctions is critical to target pathological angiogenesis. Given the conflicting role of bioactive lipids reported in the current literature, the goal of this review is to provide the reader a clear road map of what has been accomplished so far in the field with specific focus on the role of polyunsaturated fatty acids (PUFAs)-derived metabolites in proliferative retinopathies. This necessarily entails a description of the different retina cells, blood retina barriers and the role of (PUFAs)-derived metabolites in diabetic retinopathy, retinopathy of prematurity and age-related macular degeneration as the most common types of proliferative retinopathies.
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Affiliation(s)
- Khaled Elmasry
- Department of Oral Biology and Diagnostic Sciences, Dental College of Georgia, Augusta University, Augusta, GA, USA
- Cellular Biology and Anatomy, MCG, Augusta University, Augusta, GA, USA
- Department of Anatomy, Faculty of Medicine, Mansoura University, Mansoura, Egypt
- Schepens Eye Research Institute/Massachusetts Eye and Ear & Department of ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Ahmed S Ibrahim
- Department of Oral Biology and Diagnostic Sciences, Dental College of Georgia, Augusta University, Augusta, GA, USA
- Department of Biochemistry, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt
- Department of Ophthalmology and Culver Vision Discovery Institute, Medical College of Georgia (MCG), Augusta University, Augusta, GA, USA
| | - Samer Abdulmoneim
- Department of Oral Biology and Diagnostic Sciences, Dental College of Georgia, Augusta University, Augusta, GA, USA
- Cellular Biology and Anatomy, MCG, Augusta University, Augusta, GA, USA
| | - Mohamed Al-Shabrawey
- Department of Oral Biology and Diagnostic Sciences, Dental College of Georgia, Augusta University, Augusta, GA, USA
- Cellular Biology and Anatomy, MCG, Augusta University, Augusta, GA, USA
- Department of Anatomy, Faculty of Medicine, Mansoura University, Mansoura, Egypt
- Department of Ophthalmology and Culver Vision Discovery Institute, Medical College of Georgia (MCG), Augusta University, Augusta, GA, USA
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25
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Wang Y, Hao N, Lin H, Wang T, Xie J, Yuan Y. Down-regulation of CASK in glucotoxicity-induced insulin dysfunction in pancreatic β cells. Acta Biochim Biophys Sin (Shanghai) 2018; 50:281-287. [PMID: 29293883 DOI: 10.1093/abbs/gmx139] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 12/08/2017] [Indexed: 12/28/2022] Open
Abstract
High-glucose level exerts deleterious effects on pancreatic β cells, but the mechanisms remain unclear. Calcium/calmodulin-dependent serine protein kinase (CASK) plays a vital role in neural development and release of neurotransmitters, and probably plays a role in the anchoring of insulin on pancreatic β cell membrane. Hypoxia-inducible factor 1α (HIF1α) is involved in β-cell dysfunction. The aim of this study was to provide some basic evidence that CASK could be involved in glucotoxicity-induced insulin secretion dysfunction mediated by HIF1α in INS-1E cells. CASK overexpression plasmid, HIF1α agonist (CoCl2), and HIF1α selective inhibitor (KC7F2) were used. The results showed that chronic stimulation with high glucose could induce insulin secretion dysfunction in INS-1E β cells. Overexpression of CASK partially reversed the effects of high glucose on insulin secretion. CoCl2 reduced the expression of CASK, but KC7F2 reversed the glucotoxicity-induced CASK level reduction. These results suggested that glucotoxicity-induced insulin secretion defects in INS-1E cells could be mediated by HIF1α via the down-regulation of CASK.
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Affiliation(s)
- Yao Wang
- Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, Southeast University, Nanjing 210009, China
| | - Nana Hao
- Department of Endocrinology, Affiliated Fuyang Hospital of Anhui Medical University, Fuyang 236000, China
| | - Haiyan Lin
- Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing 211166, China
| | - Tianyuan Wang
- Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, Southeast University, Nanjing 210009, China
| | - Jinyang Xie
- Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, Southeast University, Nanjing 210009, China
| | - Yuexing Yuan
- Department of Endocrinology, Zhongda Hospital, Institute of Diabetes, Southeast University, Nanjing 210009, China
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26
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Bensellam M, Jonas JC, Laybutt DR. Mechanisms of β-cell dedifferentiation in diabetes: recent findings and future research directions. J Endocrinol 2018; 236:R109-R143. [PMID: 29203573 DOI: 10.1530/joe-17-0516] [Citation(s) in RCA: 149] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 12/04/2017] [Indexed: 12/13/2022]
Abstract
Like all the cells of an organism, pancreatic β-cells originate from embryonic stem cells through a complex cellular process termed differentiation. Differentiation involves the coordinated and tightly controlled activation/repression of specific effectors and gene clusters in a time-dependent fashion thereby giving rise to particular morphological and functional cellular features. Interestingly, cellular differentiation is not a unidirectional process. Indeed, growing evidence suggests that under certain conditions, mature β-cells can lose, to various degrees, their differentiated phenotype and cellular identity and regress to a less differentiated or a precursor-like state. This concept is termed dedifferentiation and has been proposed, besides cell death, as a contributing factor to the loss of functional β-cell mass in diabetes. β-cell dedifferentiation involves: (1) the downregulation of β-cell-enriched genes, including key transcription factors, insulin, glucose metabolism genes, protein processing and secretory pathway genes; (2) the concomitant upregulation of genes suppressed or expressed at very low levels in normal β-cells, the β-cell forbidden genes; and (3) the likely upregulation of progenitor cell genes. These alterations lead to phenotypic reconfiguration of β-cells and ultimately defective insulin secretion. While the major role of glucotoxicity in β-cell dedifferentiation is well established, the precise mechanisms involved are still under investigation. This review highlights the identified molecular mechanisms implicated in β-cell dedifferentiation including oxidative stress, endoplasmic reticulum (ER) stress, inflammation and hypoxia. It discusses the role of Foxo1, Myc and inhibitor of differentiation proteins and underscores the emerging role of non-coding RNAs. Finally, it proposes a novel hypothesis of β-cell dedifferentiation as a potential adaptive mechanism to escape cell death under stress conditions.
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Affiliation(s)
- Mohammed Bensellam
- Garvan Institute of Medical ResearchSydney, New South Wales, Australia
- Université Catholique de LouvainInstitut de Recherche Expérimentale et Clinique, Pôle d'Endocrinologie, Diabète et Nutrition, Brussels, Belgium
| | - Jean-Christophe Jonas
- Université Catholique de LouvainInstitut de Recherche Expérimentale et Clinique, Pôle d'Endocrinologie, Diabète et Nutrition, Brussels, Belgium
| | - D Ross Laybutt
- Garvan Institute of Medical ResearchSydney, New South Wales, Australia
- St Vincent's Clinical SchoolUNSW Sydney, Sydney, New South Wales, Australia
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27
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Aguayo-Mazzucato C, Bonner-Weir S. Pancreatic β Cell Regeneration as a Possible Therapy for Diabetes. Cell Metab 2018; 27:57-67. [PMID: 28889951 PMCID: PMC5762410 DOI: 10.1016/j.cmet.2017.08.007] [Citation(s) in RCA: 149] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 07/05/2017] [Accepted: 08/08/2017] [Indexed: 02/08/2023]
Abstract
Diabetes is the result of having inadequate supply of functional insulin-producing β cells. Two possible approaches for replenishing the β cells are: (1) replacement by transplanting cadaveric islets or β cells derived from human embryonic stem cells/induced pluripotent stem cells and (2) induction of endogenous regeneration. This review focuses on endogenous regeneration, which can follow two pathways: enhanced replication of existing β cells and formation of new β cells from cells not expressing insulin, either by conversion from a differentiated cell type (transdifferentiation) or differentiation from progenitors (neogenesis). Exciting progress on both pathways suggest that regeneration may have therapeutic promise.
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Affiliation(s)
| | - Susan Bonner-Weir
- Joslin Diabetes Center, Harvard Medical School, Harvard Stem Cell Institute, Boston, MA 02215, USA.
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28
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Tritschler S, Theis FJ, Lickert H, Böttcher A. Systematic single-cell analysis provides new insights into heterogeneity and plasticity of the pancreas. Mol Metab 2017; 6:974-990. [PMID: 28951822 PMCID: PMC5605721 DOI: 10.1016/j.molmet.2017.06.021] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 06/13/2017] [Accepted: 06/19/2017] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Diabetes mellitus is characterized by loss or dysfunction of insulin-producing β-cells in the pancreas, resulting in failure of blood glucose regulation and devastating secondary complications. Thus, β-cells are currently the prime target for cell-replacement and regenerative therapy. Triggering endogenous repair is a promising strategy to restore β-cell mass and normoglycemia in diabetic patients. Potential strategies include targeting specific β-cell subpopulations to increase proliferation or maturation. Alternatively, transdifferentiation of pancreatic islet cells (e.g. α- or δ-cells), extra-islet cells (acinar and ductal cells), hepatocytes, or intestinal cells into insulin-producing cells might improve glycemic control. To this end, it is crucial to systematically characterize and unravel the transcriptional program of all pancreatic cell types at the molecular level in homeostasis and disease. Furthermore, it is necessary to better determine the underlying mechanisms of β-cell maturation, maintenance, and dysfunction in diabetes, to identify and molecularly profile endocrine subpopulations with regenerative potential, and to translate the findings from mice to man. Recent approaches in single-cell biology started to illuminate heterogeneity and plasticity in the pancreas that might be targeted for β-cell regeneration in diabetic patients. SCOPE OF REVIEW This review discusses recent literature on single-cell analysis including single-cell RNA sequencing, single-cell mass cytometry, and flow cytometry of pancreatic cell types in the context of mechanisms of endogenous β-cell regeneration. We discuss new findings on the regulation of postnatal β-cell proliferation and maturation. We highlight how single-cell analysis recapitulates described principles of functional β-cell heterogeneity in animal models and adds new knowledge on the extent of β-cell heterogeneity in humans as well as its role in homeostasis and disease. Furthermore, we summarize the findings on cell subpopulations with regenerative potential that might enable the formation of new β-cells in diseased state. Finally, we review new data on the transcriptional program and function of rare pancreatic cell types and their implication in diabetes. MAJOR CONCLUSION Novel, single-cell technologies offer high molecular resolution of cellular heterogeneity within the pancreas and provide information on processes and factors that govern β-cell homeostasis, proliferation, and maturation. Eventually, these technologies might lead to the characterization of cells with regenerative potential and unravel disease-associated changes in gene expression to identify cellular and molecular targets for therapy.
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Affiliation(s)
- Sophie Tritschler
- Institute of Diabetes and Regeneration Research, Helmholtz Zentrum München, Am Parkring 11, 85748 Garching-Hochbrück, Germany
- German Center for Diabetes Research, 85764 Neuherberg, Germany
- Institute of Computational Biology, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Fabian J. Theis
- Institute of Computational Biology, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Heiko Lickert
- Institute of Diabetes and Regeneration Research, Helmholtz Zentrum München, Am Parkring 11, 85748 Garching-Hochbrück, Germany
- German Center for Diabetes Research, 85764 Neuherberg, Germany
- Institute of Stem Cell Research, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Anika Böttcher
- Institute of Diabetes and Regeneration Research, Helmholtz Zentrum München, Am Parkring 11, 85748 Garching-Hochbrück, Germany
- German Center for Diabetes Research, 85764 Neuherberg, Germany
- Institute of Stem Cell Research, Helmholtz Zentrum München, 85764 Neuherberg, Germany
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29
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Barakat G, Moustafa ME, Khalifeh I, Hodroj MH, Bikhazi A, Rizk S. Effects of exendin-4 and selenium on the expression of GLP-1R, IRS-1, and preproinsulin in the pancreas of diabetic rats. J Physiol Biochem 2017; 73:387-394. [PMID: 28589533 DOI: 10.1007/s13105-017-0565-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 05/23/2017] [Indexed: 03/23/2024]
Abstract
The mechanisms by which exendin-4 and selenium exert their antidiabetic actions are still unclear. Here, we investigated the effects of exendin-4 or selenium administration on the expression of glucagon-like peptide-1 receptor (GLP-1R), insulin receptor substrate-1 (IRS-1), and preproinsulin in the pancreas of diabetic rats. Diabetes was induced by streptozotocin administration. Diabetic rats were injected intraperitoneally with 0.03 μg exendin-4/kg body weight/daily or treated with 5 ppm selenium in drinking water for a period of 4 weeks. GLP-1R and IRS-1 levels were decreased while the level of preproinsulin messenger RNA (mRNA) was increased in the pancreas of diabetic untreated rats, as compared to that in control rats. Treatment of diabetic rats with exendin-4 increased protein and mRNA levels of GLP-1R, and IRS-1, and the mRNA level of preproinsulin in the pancreas, as compared to their levels in diabetic untreated rats. Selenium treatment of diabetic rats increased the pancreatic mRNA levels of GLP-1R, IRS-1, and preproinsulin. Exendin-4 or selenium treatment of diabetic rats also increased the numbers of pancreatic islets and GLP-1R molecules in the pancreas. Therefore, exendin-4 and selenium may exert their antidiabetic effects by increasing GLP-1R, IRS-1, and preproinsulin expression in the pancreas and by increasing the number of pancreatic islets.
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Affiliation(s)
- Ghinwa Barakat
- Department of Biological Sciences, Faculty of Science, Beirut Arab University, Beirut, Lebanon
| | - Mohamed E Moustafa
- Department of Biological Sciences, Faculty of Science, Beirut Arab University, Beirut, Lebanon.,Department of Biochemistry, Faculty of Science, Alexandria University, Alexandria, Egypt
| | - Ibrahim Khalifeh
- Department of Pathology Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Mohammad H Hodroj
- Department of Natural Sciences, Lebanese American University, Beirut, 1102-2801, Lebanon
| | - Anwar Bikhazi
- Department of Physiology Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Sandra Rizk
- Department of Natural Sciences, Lebanese American University, Beirut, 1102-2801, Lebanon.
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30
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Eulálio JMR, Bon-Habib ACC, Soares DDO, Corrêa PGA, Pineschi GPF, Diniz VS, Manso JEF, Schanaider A. Critical analysis and systematization of rat pancreatectomy terminology. Acta Cir Bras 2017; 31:698-704. [PMID: 27828605 DOI: 10.1590/s0102-865020160100000010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 09/16/2016] [Indexed: 11/22/2022] Open
Abstract
PURPOSE: To critically analyze and standardize the rat pancreatectomy nomenclature variants. METHODS: It was performed a review of indexed manuscripts in PUBMED from 01/01/1945 to 31/12/2015 with the combined keywords "rat pancreatectomy" and "rat pancreas resection". The following parameters was considered: A. Frequency of publications; B. Purpose of the pancreatectomy in each article; C. Bibliographic references; D. Nomenclature of techniques according to the pancreatic parenchyma resection percentage. RESULTS: Among the 468, the main objectives were to surgically induce diabetes and to study the genes regulations and expressions. Five rat pancreatectomy technique references received 15 or more citations. Twenty different terminologies were identified for the pancreas resection: according to the resected parenchyma percentage (30 to 95%); to the procedure type (total, subtotal and partial); or based on the selected anatomical region (distal, longitudinal and segmental). A nomenclature systematization was gathered by cross-checking information between the main surgical techniques, the anatomic parameters descriptions and the resected parenchyma percentages. CONCLUSION: The subtotal pancreatectomy nomenclature for parenchymal resection between 80 and 95% establishes a surgical parameter that also defines the total and partial pancreatectomy limits and standardizes these surgical procedures in rats.
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Affiliation(s)
- José Marcus Raso Eulálio
- PhD, Assistant Professor, Head of Division, Department of Surgery, School of Medicine, Universidade Federal do Rio de Janeiro (UFRJ), Brazil. Conception and design of the study, interpretation of data, manuscript preparation and writing
| | - Assad Charbel Chequer Bon-Habib
- Graduate student, Scientific Initiation, Department of Surgery, School of Medicine, UFRJ, Rio de Janeiro-RJ, Brail. Acquisition, analysis and interpretation of data
| | - Daiane de Oliveira Soares
- Graduate student, Scientific Initiation, Department of Surgery, School of Medicine, UFRJ, Rio de Janeiro-RJ, Brail. Acquisition, analysis and interpretation of data
| | - Paulo Guilherme Antunes Corrêa
- Graduate student, Scientific Initiation, Department of Surgery, School of Medicine, UFRJ, Rio de Janeiro-RJ, Brail. Acquisition, analysis and interpretation of data
| | - Giovana Penna Firme Pineschi
- Graduate student, Scientific Initiation, Department of Surgery, School of Medicine, UFRJ, Rio de Janeiro-RJ, Brail. Acquisition, analysis and interpretation of data
| | - Victor Senna Diniz
- Graduate student, Scientific Initiation, Department of Surgery, School of Medicine, UFRJ, Rio de Janeiro-RJ, Brail. Acquisition, analysis and interpretation of data
| | - José Eduardo Ferreira Manso
- PhD, Associate Professor, Head, Department of Surgery, Postgraduate Program in Surgical Sciences, School of Medicine, UFRJ, Rio de Janeiro-RJ, Brazil. Acquisition and interpretation of data
| | - Alberto Schanaider
- PhD, Full Professor, Head, Center of Experimental Surgical. Coordinator, Postgraduate Program in Surgical Sciences, Department of Surgery, School of Medicine, UFRJ, Rio de Janeiro-RJ, Brazil. Manuscript writing, critical revision
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31
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Wang W, Liu C, Jimenez-Gonzalez M, Song WJ, Hussain MA. The undoing and redoing of the diabetic β-cell. J Diabetes Complications 2017; 31:912-917. [PMID: 28242267 PMCID: PMC5450161 DOI: 10.1016/j.jdiacomp.2017.01.028] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 12/23/2016] [Accepted: 01/31/2017] [Indexed: 02/08/2023]
Abstract
A hallmark of type 2 diabetes (T2DM) is the reduction in functional β-cell mass, which is considered at least in part to result from an imbalance of β-cell renewal and apoptosis, with the latter being accelerated during metabolic stress. More recent studies, however, suggest that the loss of functional β-cell mass is not as much due to β-cell death but rather to de-differentiation of β-cells when these cells are exposed to metabolic stressors, opening the possibility to re-differentiate and restore functional β-cell mass by therapeutic intervention. In parallel, clinical observations suggest that temporary intensive insulin therapy in early diagnosed humans with T2DM, so as to "rest" endogenous β-cells, allows these patients to regain adequate insulin secretion and to maintain euglycemia for prolonged periods free of continued pharmacotherapy. Whether observations made in (mostly rodent) models of diabetes mellitus and in clinical trials are revealing identical mechanisms and therapeutic opportunities remains a tantalizing possibility. Our intention is for this review to serve as an overview of the field and commentary of this particularly exciting field of research.
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Affiliation(s)
- Wei Wang
- Metabolism Division, Departments of Pediatrics, Medicine and Biological Chemistry, Johns Hopkins University School of Medicine, 600 N Wolfe Street, CMSC 10-113, Baltimore, MD 21287
| | - Chune Liu
- Metabolism Division, Departments of Pediatrics, Medicine and Biological Chemistry, Johns Hopkins University School of Medicine, 600 N Wolfe Street, CMSC 10-113, Baltimore, MD 21287
| | - Maria Jimenez-Gonzalez
- Metabolism Division, Departments of Pediatrics, Medicine and Biological Chemistry, Johns Hopkins University School of Medicine, 600 N Wolfe Street, CMSC 10-113, Baltimore, MD 21287
| | - Woo-Jin Song
- Metabolism Division, Departments of Pediatrics, Medicine and Biological Chemistry, Johns Hopkins University School of Medicine, 600 N Wolfe Street, CMSC 10-113, Baltimore, MD 21287
| | - Mehboob A Hussain
- Metabolism Division, Departments of Pediatrics, Medicine and Biological Chemistry, Johns Hopkins University School of Medicine, 600 N Wolfe Street, CMSC 10-113, Baltimore, MD 21287.
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32
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Seshadri N, Jonasson ME, Hunt KL, Xiang B, Cooper S, Wheeler MB, Dolinsky VW, Doucette CA. Uncoupling protein 2 regulates daily rhythms of insulin secretion capacity in MIN6 cells and isolated islets from male mice. Mol Metab 2017; 6:760-769. [PMID: 28702331 PMCID: PMC5485245 DOI: 10.1016/j.molmet.2017.04.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 04/16/2017] [Accepted: 04/24/2017] [Indexed: 12/17/2022] Open
Abstract
Objective Upregulation of uncoupling protein 2 (UCP2) is associated with impaired glucose-stimulated insulin secretion (GSIS), which is thought to be an important contributor to pathological β cell failure in obesity and type 2 diabetes (T2D); however, the physiological function of UCP2 in the β cell remains undefined. It has been suggested, but not yet tested, that UCP2 plays a physiological role in β cells by coordinating insulin secretion capacity with anticipated fluctuating nutrient supply, such that upregulation of UCP2 in the inactive/fasted state inhibits GSIS as a mechanism to prevent hypoglycemia. Therefore, we hypothesized that daily cycles of GSIS capacity are dependent on rhythmic and predictable patterns of Ucp2 gene expression such that low Ucp2 in the active/fed phase promotes maximal GSIS capacity, whereas elevated Ucp2 expression in the inactive/fasted phase supresses GSIS capacity. We further hypothesized that rhythmic Ucp2 expression is required for the maintenance of glucose tolerance over the 24 h cycle. Methods We used synchronized MIN6 clonal β cells and isolated mouse islets from wild type (C57BL6) and mice with β cell knockout of Ucp2 (Ucp2-βKO; and respective Ins2-cre controls) to determine the endogenous expression pattern of Ucp2 over 24 h and its impact on GSIS capacity and glucose tolerance over 24 h. Results A dynamic pattern of Ucp2 mRNA expression was observed in synchronized MIN6 cells, which showed a reciprocal relationship with GSIS capacity in a time-of-day-specific manner. GSIS capacity was suppressed in islets isolated from wild type and control mice during the light/inactive phase of the daily cycle; a suppression that was dependent on Ucp2 in the β cell and was lost in islets isolated from Ucp2-βKO mice or wild type islets treated with a UCP2 inhibitor. Finally, suppression of GSIS capacity by UCP2 in the light phase was required for the maintenance of normal patterns of glucose tolerance. Conclusions Our study suggests that Ucp2/UCP2 in the β cell is part of an important, endogenous, metabolic regulator that controls the temporal capacity of GSIS over the course of the day/night cycle, which, in turn, regulates time-of-day glucose tolerance. Targeting Ucp2/UCP2 as a therapeutic in type 2 diabetes or any other metabolic condition must take into account the rhythmic nature of its expression and its impact on glucose tolerance over 24 h, specifically during the inactive/fasted phase. Ucp2 mRNA expression in MIN6 β cells and isolated islets is dynamic and rhythmic over 24 h. Daily cycles of glucose-stimulated insulin secretion capacity are dependent on rhythmic Ucp2 expression and UCP2 activity. Loss of rhythmic Ucp2 mRNA expression triggers glucose intolerance only in the light/inactive phase of the daily cycle. UCP2 is part of an endogenous diurnal metabolic regulator that coordinates islet function with the daily cycle of fasting and feeding.
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Key Words
- GSIS, Glucose-stimulated insulin secretion
- Glucose tolerance
- Glucose-stimulated insulin secretion
- HG, High glucose
- Ins2-cre, Ins2 promoter-driven cre recombinase
- LG, Low glucose
- MIN6, Mouse insulinoma 6
- Pancreatic islets
- T2D, Type 2 diabetes
- UCP2, Uncoupling protein 2
- Ucp2-βKO, β cell-specific Ucp2 knockout
- Uncoupling protein 2
- WT, wild type
- ZT, Zeitgeber time
- i.p.GTT, intraperitoneal glucose tolerance test
- β cells
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Affiliation(s)
- Nivedita Seshadri
- Univerisity of Manitoba, Department of Physiology and Pathophysiology, Winnipeg, MB, R3E 0J9, Canada.,The Children's Hospital Research Institute of Manitoba, Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme, Winnipeg, MB, R3E 3P4, Canada
| | - Michael E Jonasson
- The Children's Hospital Research Institute of Manitoba, Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme, Winnipeg, MB, R3E 3P4, Canada
| | - Kristin L Hunt
- Univerisity of Manitoba, Department of Physiology and Pathophysiology, Winnipeg, MB, R3E 0J9, Canada.,The Children's Hospital Research Institute of Manitoba, Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme, Winnipeg, MB, R3E 3P4, Canada
| | - Bo Xiang
- The Children's Hospital Research Institute of Manitoba, Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme, Winnipeg, MB, R3E 3P4, Canada.,University of Manitoba, Department of Pharmacology & Therapeutics, Winnipeg, MB, R3E 0T6, Canada
| | - Steven Cooper
- The Children's Hospital Research Institute of Manitoba, Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme, Winnipeg, MB, R3E 3P4, Canada
| | - Michael B Wheeler
- University of Toronto, Department of Physiology, Toronto, ON, M5S 1A8, Canada
| | - Vernon W Dolinsky
- The Children's Hospital Research Institute of Manitoba, Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme, Winnipeg, MB, R3E 3P4, Canada.,University of Manitoba, Department of Pharmacology & Therapeutics, Winnipeg, MB, R3E 0T6, Canada
| | - Christine A Doucette
- Univerisity of Manitoba, Department of Physiology and Pathophysiology, Winnipeg, MB, R3E 0J9, Canada.,The Children's Hospital Research Institute of Manitoba, Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme, Winnipeg, MB, R3E 3P4, Canada
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Kim JW, You YH, Ham DS, Yang HK, Yoon KH. The Paradoxical Effects of AMPK on Insulin Gene Expression and Glucose-Induced Insulin Secretion. J Cell Biochem 2016; 117:239-46. [PMID: 26105159 DOI: 10.1002/jcb.25271] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 06/19/2015] [Indexed: 12/23/2022]
Abstract
The activation of AMP-activated protein kinase (AMPK) is known to repress the expression of the insulin gene and glucose-stimulated insulin secretion (GSIS). However, the mechanisms by which this occurs, as well as the effects of AMPK activation on glucolipotoxicity-induced β-cell dysfunction, have not been elucidated. To investigate the effects of 5-amino-4-imidazolecarboxamide ribonucleotide (AICAR) and peroxisome proliferator-activated receptorγ-coactivator-1α (PGC-1α) on β-cell-specific genes under glucolipotoxic conditions, we performed real-time PCR and measured insulin secretion by primary islets. To study these effects in vivo, we administered AICAR for 10 days (1 mg/g body weight) to 90% pancreatectomized hyperglycemic mice. The exposure of isolated rat and human islets to glucolipotoxic conditions and the overexpression of PGC-1α suppressed insulin and NEUROD1 mRNA expression. However, the expression of these genes was preserved by AICAR treatment and by PGC-1α inhibition. Exposure of isolated islets to glucolipotoxic conditions for 3 days decreased GSIS, which was also well maintained by AICAR treatment and by PGC-1α inhibition. The administration of AICAR to 90% pancreatectomized hyperglycemic mice improved glucose tolerance and insulin secretion. These results indicate that treatment of islets with an AMPK agonist under glucolipotoxic conditions protects against glucolipotoxicity-induced β-cell dysfunction. A better understanding of the functions of molecules such as PGC-1α and AMPK, which play key roles in intracellular fuel regulation, could herald a new era for the treatment of patients with type 2 diabetes mellitus by providing protection against glucolipotoxicity.
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Affiliation(s)
- Ji-Won Kim
- Department of Endocrinology & Metabolism, The Catholic University of Korea, Seoul, 137-040, Korea
| | - Young-Hye You
- Department of Endocrinology & Metabolism, The Catholic University of Korea, Seoul, 137-040, Korea
| | - Dong-Sik Ham
- Department of Endocrinology & Metabolism, The Catholic University of Korea, Seoul, 137-040, Korea
| | - Hae Kyung Yang
- Department of Endocrinology & Metabolism, The Catholic University of Korea, Seoul, 137-040, Korea
| | - Kun-Ho Yoon
- Department of Endocrinology & Metabolism, The Catholic University of Korea, Seoul, 137-040, Korea
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Armstrong M, van Hoorebeke C, Horn T, Deschamps J, Freedman JC, Kalyanaraman C, Jacobson MP, Holman T. Human 15-LOX-1 active site mutations alter inhibitor binding and decrease potency. Bioorg Med Chem 2016; 24:5380-5387. [PMID: 27647374 DOI: 10.1016/j.bmc.2016.08.063] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Revised: 08/25/2016] [Accepted: 08/29/2016] [Indexed: 12/17/2022]
Abstract
Human 15-lipoxygenase-1 (h15-LOX-1 or h12/15-LOX) reacts with polyunsaturated fatty acids and produces bioactive lipid derivatives that are implicated in many important human diseases. One such disease is stroke, which is the fifth leading cause of death and the first leading cause of disability in America. The discovery of h15-LOX-1 inhibitors could potentially lead to novel therapeutics in the treatment of stroke, however, little is known about the inhibitor/active site interaction. This study utilizes site-directed mutagenesis, guided in part by molecular modeling, to gain a better structural understanding of inhibitor interactions within the active site. We have generated eight mutants (R402L, R404L, F414I, F414W, E356Q, Q547L, L407A, I417A) of h15-LOX-1 to determine whether these active site residues interact with two h15-LOX-1 inhibitors, ML351 and an ML094 derivative, compound 18. IC50 values and steady-state inhibition kinetics were determined for the eight mutants, with four of the mutants affecting inhibitor potency relative to wild type h15-LOX-1 (F414I, F414W, E356Q and L407A). The data indicate that ML351 and compound 18, bind in a similar manner in the active site to an aromatic pocket close to F414 but have subtle differences in their specific binding modes. This information establishes the binding mode for ML094 and ML351 and will be leveraged to develop next-generation inhibitors.
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Affiliation(s)
- Michelle Armstrong
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA 95064, United States
| | - Christopher van Hoorebeke
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA 95064, United States
| | - Thomas Horn
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA 95064, United States
| | - Joshua Deschamps
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA 95064, United States
| | - J Cody Freedman
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA 95064, United States
| | - Chakrapani Kalyanaraman
- Department of Pharmaceutical Chemistry, School of Pharmacy, University of California San Francisco, San Francisco, CA 94143, United States
| | - Matthew P Jacobson
- Department of Pharmaceutical Chemistry, School of Pharmacy, University of California San Francisco, San Francisco, CA 94143, United States
| | - Theodore Holman
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA 95064, United States.
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Ackermann JA, Hofheinz K, Zaiss MM, Krönke G. The double-edged role of 12/15-lipoxygenase during inflammation and immunity. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1862:371-381. [PMID: 27480217 DOI: 10.1016/j.bbalip.2016.07.014] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 07/01/2016] [Accepted: 07/28/2016] [Indexed: 01/18/2023]
Abstract
12/15-Lipoxygenase (12/15-LOX) mediates the enzymatic oxidation of polyunsaturated fatty acids, thereby contributing to the generation of various bioactive lipid mediators. Although 12/15-LOX has been implicated in the pathogenesis of multiple chronic inflammatory diseases, its physiologic functions seem to include potent immune modulatory properties that physiologically contribute to the resolution of inflammation and the clearance of inflammation-associated tissue damage. This review aims to give a comprehensive overview about our current knowledge on the role of this enzyme during the regulation of inflammation and immunity. This article is part of a Special Issue entitled: Lipid modification and lipid peroxidation products in innate immunity and inflammation edited by Christoph J. Binder.
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Affiliation(s)
- Jochen A Ackermann
- Department of Internal Medicine 3 and Institute for Clinical Immunology, University Hospital Erlangen, Erlangen, Germany; Nikolaus Fiebiger Center of Molecular Medicine, University Hospital Erlangen, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Katharina Hofheinz
- Department of Internal Medicine 3 and Institute for Clinical Immunology, University Hospital Erlangen, Erlangen, Germany; Nikolaus Fiebiger Center of Molecular Medicine, University Hospital Erlangen, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Mario M Zaiss
- Department of Internal Medicine 3 and Institute for Clinical Immunology, University Hospital Erlangen, Erlangen, Germany
| | - Gerhard Krönke
- Department of Internal Medicine 3 and Institute for Clinical Immunology, University Hospital Erlangen, Erlangen, Germany; Nikolaus Fiebiger Center of Molecular Medicine, University Hospital Erlangen, University of Erlangen-Nuremberg, Erlangen, Germany.
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Bensellam M, Maxwell EL, Chan JY, Luzuriaga J, West PK, Jonas JC, Gunton JE, Laybutt DR. Hypoxia reduces ER-to-Golgi protein trafficking and increases cell death by inhibiting the adaptive unfolded protein response in mouse beta cells. Diabetologia 2016; 59:1492-1502. [PMID: 27039902 DOI: 10.1007/s00125-016-3947-y] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Accepted: 03/16/2016] [Indexed: 12/13/2022]
Abstract
AIMS/HYPOTHESIS Hypoxia may contribute to beta cell failure in type 2 diabetes and islet transplantation. The adaptive unfolded protein response (UPR) is required for endoplasmic reticulum (ER) homeostasis. Here we investigated whether or not hypoxia regulates the UPR in beta cells and the role the adaptive UPR plays during hypoxic stress. METHODS Mouse islets and MIN6 cells were exposed to various oxygen (O2) tensions. DNA-damage inducible transcript 3 (DDIT3), hypoxia-inducible transcription factor (HIF)1α and HSPA5 were knocked down using small interfering (si)RNA; Hspa5 was also overexpressed. db/db mice were used. RESULTS Hypoxia-response genes were upregulated in vivo in the islets of diabetic, but not prediabetic, db/db mice. In isolated mouse islets and MIN6 cells, O2 deprivation (1-5% vs 20%; 4-24 h) markedly reduced the expression of adaptive UPR genes, including Hspa5, Hsp90b1, Fkbp11 and spliced Xbp1. Coatomer protein complex genes (Copa, Cope, Copg [also known as Copg1], Copz1 and Copz2) and ER-to-Golgi protein trafficking were also reduced, whereas apoptotic genes (Ddit3, Atf3 and Trb3 [also known as Trib3]), c-Jun N-terminal kinase (JNK) phosphorylation and cell death were increased. Inhibition of JNK, but not HIF1α, restored adaptive UPR gene expression and ER-to-Golgi protein trafficking while protecting against apoptotic genes and cell death following hypoxia. DDIT3 knockdown delayed the loss of the adaptive UPR and partially protected against hypoxia-induced cell death. The latter response was prevented by HSPA5 knockdown. Finally, Hspa5 overexpression significantly protected against hypoxia-induced cell death. CONCLUSIONS/INTERPRETATION Hypoxia inhibits the adaptive UPR in beta cells via JNK and DDIT3 activation, but independently of HIF1α. Downregulation of the adaptive UPR contributes to reduced ER-to-Golgi protein trafficking and increased beta cell death during hypoxic stress.
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Affiliation(s)
- Mohammed Bensellam
- Garvan Institute of Medical Research, St Vincent's Hospital, UNSW Australia, 384 Victoria Street, Darlinghurst, Sydney, NSW, 2010, Australia
| | - Emma L Maxwell
- Garvan Institute of Medical Research, St Vincent's Hospital, UNSW Australia, 384 Victoria Street, Darlinghurst, Sydney, NSW, 2010, Australia
| | - Jeng Yie Chan
- Garvan Institute of Medical Research, St Vincent's Hospital, UNSW Australia, 384 Victoria Street, Darlinghurst, Sydney, NSW, 2010, Australia
| | - Jude Luzuriaga
- Garvan Institute of Medical Research, St Vincent's Hospital, UNSW Australia, 384 Victoria Street, Darlinghurst, Sydney, NSW, 2010, Australia
| | - Phillip K West
- Garvan Institute of Medical Research, St Vincent's Hospital, UNSW Australia, 384 Victoria Street, Darlinghurst, Sydney, NSW, 2010, Australia
| | - Jean-Christophe Jonas
- Université catholique de Louvain, Institut de recherche expérimentale et clinique, Pôle d'endocrinologie, diabète et nutrition, Brussels, Belgium
| | - Jenny E Gunton
- Garvan Institute of Medical Research, St Vincent's Hospital, UNSW Australia, 384 Victoria Street, Darlinghurst, Sydney, NSW, 2010, Australia
- Westmead Hospital, Sydney, NSW, Australia
- The Westmead Millennium Institute for Medical Research, The University of Sydney, Sydney, NSW, Australia
| | - D Ross Laybutt
- Garvan Institute of Medical Research, St Vincent's Hospital, UNSW Australia, 384 Victoria Street, Darlinghurst, Sydney, NSW, 2010, Australia.
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Hormetic and regulatory effects of lipid peroxidation mediators in pancreatic beta cells. Mol Aspects Med 2016; 49:49-77. [PMID: 27012748 DOI: 10.1016/j.mam.2016.03.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2015] [Revised: 02/23/2016] [Accepted: 03/09/2016] [Indexed: 12/12/2022]
Abstract
Nutrient sensing mechanisms of carbohydrates, amino acids and lipids operate distinct pathways that are essential for the adaptation to varying metabolic conditions. The role of nutrient-induced biosynthesis of hormones is paramount for attaining metabolic homeostasis in the organism. Nutrient overload attenuate key metabolic cellular functions and interfere with hormonal-regulated inter- and intra-organ communication, which may ultimately lead to metabolic derangements. Hyperglycemia and high levels of saturated free fatty acids induce excessive production of oxygen free radicals in tissues and cells. This phenomenon, which is accentuated in both type-1 and type-2 diabetic patients, has been associated with the development of impaired glucose tolerance and the etiology of peripheral complications. However, low levels of the same free radicals also induce hormetic responses that protect cells against deleterious effects of the same radicals. Of interest is the role of hydroxyl radicals in initiating peroxidation of polyunsaturated fatty acids (PUFA) and generation of α,β-unsaturated reactive 4-hydroxyalkenals that avidly form covalent adducts with nucleophilic moieties in proteins, phospholipids and nucleic acids. Numerous studies have linked the lipid peroxidation product 4-hydroxy-2E-nonenal (4-HNE) to different pathological and cytotoxic processes. Similarly, two other members of the family, 4-hydroxyl-2E-hexenal (4-HHE) and 4-hydroxy-2E,6Z-dodecadienal (4-HDDE), have also been identified as potential cytotoxic agents. It has been suggested that 4-HNE-induced modifications in macromolecules in cells may alter their cellular functions and modify signaling properties. Yet, it has also been acknowledged that these bioactive aldehydes also function as signaling molecules that directly modify cell functions in a hormetic fashion to enable cells adapt to various stressful stimuli. Recent studies have shown that 4-HNE and 4-HDDE, which activate peroxisome proliferator-activated receptor δ (PPARδ) in vascular endothelial cells and insulin secreting beta cells, promote such adaptive responses to ameliorate detrimental effects of high glucose and diabetes-like conditions. In addition, due to the electrophilic nature of these reactive aldehydes they form covalent adducts with electronegative moieties in proteins, phosphatidylethanolamine and nucleotides. Normally these non-enzymatic modifications are maintained below the cytotoxic range due to efficient cellular neutralization processes of 4-hydroxyalkenals. The major neutralizing enzymes include fatty aldehyde dehydrogenase (FALDH), aldose reductase (AR) and alcohol dehydrogenase (ADH), which transform the aldehyde to the corresponding carboxylic acid or alcohols, respectively, or by biding to the thiol group in glutathione (GSH) by the action of glutathione-S-transferase (GST). This review describes the hormetic and cytotoxic roles of oxygen free radicals and 4-hydroxyalkenals in beta cells exposed to nutritional challenges and the cellular mechanisms they employ to maintain their level at functional range below the cytotoxic threshold.
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Ye W, Zheng Y, Zhang S, Yan L, Cheng H, Wu M. Oxamate Improves Glycemic Control and Insulin Sensitivity via Inhibition of Tissue Lactate Production in db/db Mice. PLoS One 2016; 11:e0150303. [PMID: 26938239 PMCID: PMC4777529 DOI: 10.1371/journal.pone.0150303] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 02/02/2016] [Indexed: 12/18/2022] Open
Abstract
Oxamate (OXA) is a pyruvate analogue that directly inhibits the lactate dehydrogenase (LDH)-catalyzed conversion process of pyruvate into lactate. Earlier and recent studies have shown elevated blood lactate levels among insulin-resistant and type 2 diabetes subjects and that blood lactate levels independently predicted the development of incident diabetes. To explore the potential of OXA in the treatment of diabetes, db/db mice were treated with OXA in vivo. Treatment of OXA (350–750 mg/kg of body weight) for 12 weeks was shown to decrease body weight gain and blood glucose and HbA1c levels and improve insulin secretion, the morphology of pancreatic islets, and insulin sensitivity in db/db mice. Meanwhile, OXA reduced the lactate production of adipose tissue and skeletal muscle and serum lactate levels and decreased serum levels of TG, FFA, CRP, IL-6, and TNF-α in db/db mice. The PCR array showed that OXA downregulated the expression of Tnf, Il6, leptin, Cxcr3, Map2k1, and Ikbkb, and upregulated the expression of Irs2, Nfkbia, and Pde3b in the skeletal muscle of db/db mice. Interestingly, LDH-A expression increased in the islet cells of db/db mice, and both treatment of OXA and pioglitazone decreased LDH-A expression, which might be related to the improvement of insulin secretion. Taken together, increased lactate production of adipose tissue and skeletal muscle may be at least partially responsible for insulin resistance and diabetes in db/db mice. OXA improved glycemic control and insulin sensitivity in db/db mice primarily via inhibition of tissue lactate production. Oxamic acid derivatives may be a potential drug for the treatment of type 2 diabetes.
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Affiliation(s)
- Weiran Ye
- Department of Endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, P. R. China
| | - Yijia Zheng
- Department of Endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, P. R. China
| | - Shanshan Zhang
- Department of Endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, P. R. China
| | - Li Yan
- Department of Endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, P. R. China
| | - Hua Cheng
- Department of Endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, P. R. China
| | - Muchao Wu
- Department of Endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, P. R. China
- * E-mail:
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Eltony SA, Elmottaleb NA, Gomaa AM, Anwar MM, El-Metwally TH. Effect of All-Trans Retinoic Acid on the Pancreas of Streptozotocin-Induced Diabetic Rat. Anat Rec (Hoboken) 2016; 299:334-51. [PMID: 26704900 DOI: 10.1002/ar.23307] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 10/31/2015] [Accepted: 11/05/2015] [Indexed: 12/25/2022]
Abstract
All-trans Retinoic acid (atRA) is instructive for the development of endocrine pancreas and is an integral component of β-cell induction protocols. We showed that atRA induces glucose-responsive endocrine transdifferentiation of pleomorphic pancreatic ductal adenocarcinoma cells in vitro. This study aimed to detect the role of atRA in improving the histological changes of the pancreas in diabetic rats. Forty young male Wistar rats were used and divided into three groups. Group I: normal vehicle control (N = 5). Group II: streptozotocin-induced diabetic rats (N = 20) were followed up at 0.0, 1, 2, and 4 weeks. Group III: streptozotocin-induced diabetic rats (N = 15) treated with atRA (2.5 mg/kg/day), were followed up at 1, 2, and 4 weeks. Specimens from the pancreas were processed for light, electron microscopy and pancreatic insulin mRNA expression. Blood samples were assayed for the levels of glucose, insulin, and total peroxides. In the atRA-treated group, the number of the islets and the islet area significantly increased. Strong insulin-immunoreactive endocrine-like cells were observed nearby the pancreatic acini and the interlobular ducts. Interestingly, insulin-positive cells seemed to arise from pancreatic acinar and ductal epithelium. Ultrastructurally, ß-cells, acinar, and ductal cells restored their normal appearance. Pancreatic insulin mRNA and blood indices were almost normalized. AtRA improved the histological changes of the pancreas and the blood indices in diabetic rats.
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Affiliation(s)
- Sohair A Eltony
- Department of Histology and Cell Biology, Faculty of Medicine, Assiut University, Egypt
| | - Nashwa A Elmottaleb
- Department of Medical Physiology, Faculty of Medicine, Assiut University, Egypt
| | - Asmaa M Gomaa
- Department of Medical Physiology, Faculty of Medicine, Assiut University, Egypt
| | - Mamdouh M Anwar
- Department of Medical Physiology, Faculty of Medicine, Assiut University, Egypt
| | - Tarek H El-Metwally
- Department of Medical Biochemistry, Faculty of Medicine, Assiut University, Egypt
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Ivanov I, Kuhn H, Heydeck D. Structural and functional biology of arachidonic acid 15-lipoxygenase-1 (ALOX15). Gene 2015; 573:1-32. [PMID: 26216303 PMCID: PMC6728142 DOI: 10.1016/j.gene.2015.07.073] [Citation(s) in RCA: 149] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 06/26/2015] [Accepted: 07/21/2015] [Indexed: 12/14/2022]
Abstract
Lipoxygenases (LOX) form a family of lipid peroxidizing enzymes, which have been implicated in a number of physiological processes and in the pathogenesis of inflammatory, hyperproliferative and neurodegenerative diseases. They occur in two of the three domains of terrestrial life (bacteria, eucarya) and the human genome involves six functional LOX genes, which encode for six different LOX isoforms. One of these isoforms is ALOX15, which has first been described in rabbits in 1974 as enzyme capable of oxidizing membrane phospholipids during the maturational breakdown of mitochondria in immature red blood cells. During the following decades ALOX15 has extensively been characterized and its biological functions have been studied in a number of cellular in vitro systems as well as in various whole animal disease models. This review is aimed at summarizing the current knowledge on the protein-chemical, molecular biological and enzymatic properties of ALOX15 in various species (human, mouse, rabbit, rat) as well as its implication in cellular physiology and in the pathogenesis of various diseases.
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Affiliation(s)
- Igor Ivanov
- Institute of Biochemistry, Charité - University Medicine Berlin, Charitéplatz 1, CCO-Building, Virchowweg 6, D-10117 Berlin, Germany
| | - Hartmut Kuhn
- Institute of Biochemistry, Charité - University Medicine Berlin, Charitéplatz 1, CCO-Building, Virchowweg 6, D-10117 Berlin, Germany.
| | - Dagmar Heydeck
- Institute of Biochemistry, Charité - University Medicine Berlin, Charitéplatz 1, CCO-Building, Virchowweg 6, D-10117 Berlin, Germany
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Xiang L, Mittwede PN, Clemmer JS. Glucose Homeostasis and Cardiovascular Alterations in Diabetes. Compr Physiol 2015; 5:1815-39. [DOI: 10.1002/cphy.c150001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Orr C, Stratton J, Rao I, Al-Sayed M, Smith C, El-Shahawy M, Dafoe D, Mullen Y, Al-Abdullah I, Kandeel F. Quantifying Insulin Therapy Requirements to Preserve Islet Graft Function Following Islet Transplantation. Cell Transplant 2015; 25:83-95. [PMID: 25853639 DOI: 10.3727/096368915x687958] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
A mathematical nonlinear regression model of several parameters (baseline insulin intake, posttransplant 2-h postprandial blood glucose, and stimulated C-peptide) from type 1 diabetics with HbA1c <6.5% who do not require insulin therapy and have no hypoglycemic instances was developed for accurately predicting supplemental insulin requirements in the posttransplant period. An insulin deficit threshold of 0.018 U/kg/day was defined as the average first-year calculated insulin deficit (CID), above which HbA1c rose to >6.5% during year 2 of the posttransplant period. When insulin-untreated subjects were divided into two groups based on whether the average CID was smaller (group I) or greater (group II) than the insulin deficit threshold, HbA1c was found to be similar in the two groups in year 1, but increased significantly in group II to above 6.5% (with mean glucose of 121.9 mg/dl) but remained below 6.5% in group I subjects (with mean glucose of 108.7 mg/dl) in year 2 of the follow-up period. The greater insulin deficit in group II was also associated with a higher susceptibility to hyperglycemia during periods of low serum Rapamune and Prograf levels (combined levels below 11.2 and 4.7 ng/ml, respectively). Although the differences between predicted insulin requirement (PIR) and actual empirical insulin intake in the insulin-treated subjects were generally small, they were nonetheless sufficient to identify over- and underinsulinization at each follow-up visit for all subjects (n = 14 subjects, 135 observations). The newly developed model can effectively identify underinsulinized islet transplant recipients at risk for graft dysfunction due to inadequate supplemental insulin intake or those potentially susceptible to graft function loss due to inadequate immunosuppression. While less common following islet cell therapy, the model can also identify overinsulinized subjects who may be at risk for hypoglycemia.
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Affiliation(s)
- Chris Orr
- Southern California Islet Cell Resources Center, Department of Diabetes, Endocrinology, and Metabolism, Beckman Research Institute of the City of Hope, Duarte, CA, USA
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Tersey SA, Bolanis E, Holman TR, Maloney DJ, Nadler JL, Mirmira RG. Minireview: 12-Lipoxygenase and Islet β-Cell Dysfunction in Diabetes. Mol Endocrinol 2015; 29:791-800. [PMID: 25803446 DOI: 10.1210/me.2015-1041] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The insulin producing islet β-cells have increasingly gained attention for their role in the pathogeneses of virtually all forms of diabetes. Dysfunction, de-differentiation, and/or death of β-cells are pivotal features in the transition from normoglycemia to hyperglycemia in both animal models of metabolic disease and humans. In both type 1 and type 2 diabetes, inflammation appears to be a central cause of β-cell derangements, and molecular pathways that modulate inflammation or the inflammatory response are felt to be prime targets of future diabetes therapy. The lipoxygenases (LOs) represent a class of enzymes that oxygenate cellular polyunsaturated fatty acids to produce inflammatory lipid intermediates that directly and indirectly affect cellular function and survival. The enzyme 12-LO is expressed in all metabolically active tissues, including pancreatic islets, and has received increasing attention for its role in promoting cellular inflammation in the setting of diabetes. Genetic deletion models of 12-LO in mice reveal striking protection from metabolic disease and its complications and an emerging body of literature has implicated its role in human disease. This review focuses on the evidence supporting the proinflammatory role of 12-LO as it relates to islet β-cells, and the potential for 12-LO inhibition as a future avenue for the prevention and treatment of metabolic disease.
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Affiliation(s)
- Sarah A Tersey
- Departments of Pediatrics and the Center for Diabetes and Metabolic Diseases (S.A.T., R.G.M.), Biochemistry and Molecular Biology (E.B., R.G.M.), Medicine (R.G.M.), and Cellular and Integrative Physiology (R.G.M.), Indiana University School of Medicine, Indianapolis, Indiana 46202; Department of Chemistry and Biochemistry (T.R.H.), University of California, Santa Cruz, Santa Cruz, California 95064; National Center for Advancing Translational Sciences (D.J.M.), National Institutes of Health, Rockville, Maryland 20850; and Department of Medicine and the Strelitz Diabetes Center (J.L.N.), Eastern Virginia Medical School, Norfolk, Virginia 23507
| | - Esther Bolanis
- Departments of Pediatrics and the Center for Diabetes and Metabolic Diseases (S.A.T., R.G.M.), Biochemistry and Molecular Biology (E.B., R.G.M.), Medicine (R.G.M.), and Cellular and Integrative Physiology (R.G.M.), Indiana University School of Medicine, Indianapolis, Indiana 46202; Department of Chemistry and Biochemistry (T.R.H.), University of California, Santa Cruz, Santa Cruz, California 95064; National Center for Advancing Translational Sciences (D.J.M.), National Institutes of Health, Rockville, Maryland 20850; and Department of Medicine and the Strelitz Diabetes Center (J.L.N.), Eastern Virginia Medical School, Norfolk, Virginia 23507
| | - Theodore R Holman
- Departments of Pediatrics and the Center for Diabetes and Metabolic Diseases (S.A.T., R.G.M.), Biochemistry and Molecular Biology (E.B., R.G.M.), Medicine (R.G.M.), and Cellular and Integrative Physiology (R.G.M.), Indiana University School of Medicine, Indianapolis, Indiana 46202; Department of Chemistry and Biochemistry (T.R.H.), University of California, Santa Cruz, Santa Cruz, California 95064; National Center for Advancing Translational Sciences (D.J.M.), National Institutes of Health, Rockville, Maryland 20850; and Department of Medicine and the Strelitz Diabetes Center (J.L.N.), Eastern Virginia Medical School, Norfolk, Virginia 23507
| | - David J Maloney
- Departments of Pediatrics and the Center for Diabetes and Metabolic Diseases (S.A.T., R.G.M.), Biochemistry and Molecular Biology (E.B., R.G.M.), Medicine (R.G.M.), and Cellular and Integrative Physiology (R.G.M.), Indiana University School of Medicine, Indianapolis, Indiana 46202; Department of Chemistry and Biochemistry (T.R.H.), University of California, Santa Cruz, Santa Cruz, California 95064; National Center for Advancing Translational Sciences (D.J.M.), National Institutes of Health, Rockville, Maryland 20850; and Department of Medicine and the Strelitz Diabetes Center (J.L.N.), Eastern Virginia Medical School, Norfolk, Virginia 23507
| | - Jerry L Nadler
- Departments of Pediatrics and the Center for Diabetes and Metabolic Diseases (S.A.T., R.G.M.), Biochemistry and Molecular Biology (E.B., R.G.M.), Medicine (R.G.M.), and Cellular and Integrative Physiology (R.G.M.), Indiana University School of Medicine, Indianapolis, Indiana 46202; Department of Chemistry and Biochemistry (T.R.H.), University of California, Santa Cruz, Santa Cruz, California 95064; National Center for Advancing Translational Sciences (D.J.M.), National Institutes of Health, Rockville, Maryland 20850; and Department of Medicine and the Strelitz Diabetes Center (J.L.N.), Eastern Virginia Medical School, Norfolk, Virginia 23507
| | - Raghavendra G Mirmira
- Departments of Pediatrics and the Center for Diabetes and Metabolic Diseases (S.A.T., R.G.M.), Biochemistry and Molecular Biology (E.B., R.G.M.), Medicine (R.G.M.), and Cellular and Integrative Physiology (R.G.M.), Indiana University School of Medicine, Indianapolis, Indiana 46202; Department of Chemistry and Biochemistry (T.R.H.), University of California, Santa Cruz, Santa Cruz, California 95064; National Center for Advancing Translational Sciences (D.J.M.), National Institutes of Health, Rockville, Maryland 20850; and Department of Medicine and the Strelitz Diabetes Center (J.L.N.), Eastern Virginia Medical School, Norfolk, Virginia 23507
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Taylor-Fishwick DA, Weaver J, Glenn L, Kuhn N, Rai G, Jadhav A, Simeonov A, Dudda A, Schmoll D, Holman TR, Maloney DJ, Nadler JL. Selective inhibition of 12-lipoxygenase protects islets and beta cells from inflammatory cytokine-mediated beta cell dysfunction. Diabetologia 2015; 58:549-57. [PMID: 25417214 DOI: 10.1007/s00125-014-3452-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 10/23/2014] [Indexed: 12/30/2022]
Abstract
AIMS/HYPOTHESIS Islet inflammation leads to loss of functional pancreatic beta cell mass. Increasing evidence suggests that activation of 12-lipoxygenase leads to inflammatory beta cell loss. This study evaluates new specific small-molecule inhibitors of 12-lipoxygenase for protecting rodent and human beta cells from inflammatory damage. METHODS Mouse beta cell lines and mouse and human islets were treated with inflammatory cytokines IL-1β, TNFα and IFNγ in the absence or presence of novel selective 12-lipoxygenase inhibitors. Glucose-stimulated insulin secretion (GSIS), gene expression, cell survival and 12-S-hydroxyeicosatetraenoic acid (12-S-HETE) levels were evaluated using established methods. Pharmacokinetic analysis was performed with the lead inhibitor in CD1 mice. RESULTS Inflammatory cytokines led to the loss of human beta cell function, elevated cell death, increased inflammatory gene expression and upregulation of 12-lipoxygenase expression and activity (measured by 12-S-HETE generation). Two 12-lipoxygenase inhibitors, Compounds 5 and 9, produced a concentration-dependent reduction of stimulated 12-S-HETE levels. GSIS was preserved in the presence of the 12-lipoxygenase inhibitors. 12-Lipoxygenase inhibition preserved survival of primary mouse and human islets. When administered orally, Compound 5 reduced plasma 12-S-HETE in CD1 mice. Compounds 5 and 9 preserved the function and survival of human donor islets exposed to inflammatory cytokines. CONCLUSIONS/INTERPRETATION Selective inhibition of 12-lipoxygenase activity confers protection to beta cells during exposure to inflammatory cytokines. These concept validation studies identify 12-lipoxygenase as a promising target in the prevention of loss of functional beta cells in diabetes.
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Affiliation(s)
- David A Taylor-Fishwick
- Department of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, 700 W. Olney Road, Norfolk, VA, 23507, USA,
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Costes S, Boss M, Thomas AP, Matveyenko AV. Activation of Melatonin Signaling Promotes β-Cell Survival and Function. Mol Endocrinol 2015; 29:682-92. [PMID: 25695910 DOI: 10.1210/me.2014-1293] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Type 2 diabetes mellitus (T2DM) is characterized by pancreatic islet failure due to loss of β-cell secretory function and mass. Studies have identified a link between a variance in the gene encoding melatonin (MT) receptor 2, T2DM, and impaired insulin secretion. This genetic linkage raises the question whether MT signaling plays a role in regulation of β-cell function and survival in T2DM. To address this postulate, we used INS 832/13 cells to test whether activation of MT signaling attenuates proteotoxicity-induced β-cell apoptosis and through which molecular mechanism. We also used nondiabetic and T2DM human islets to test the potential of MT signaling to attenuate deleterious effects of glucotoxicity and T2DM on β-cell function. MT signaling in β-cells (with duration designed to mimic typical nightly exposure) significantly enhanced activation of the cAMP-dependent signal transduction pathway and attenuated proteotoxicity-induced β-cell apoptosis evidenced by reduced caspase-3 cleavage (∼40%), decreased activation of stress-activated protein kinase/Jun-amino-terminal kinase (∼50%) and diminished oxidative stress response. Activation of MT signaling in human islets was shown to restore glucose-stimulated insulin secretion in islets exposed to chronic hyperglycemia as well as in T2DM islets. Our data suggest that β-cell MT signaling is important for the regulation of β-cell survival and function and implies a preventative and therapeutic potential for preservation of β-cell mass and function in T2DM.
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Affiliation(s)
- Safia Costes
- Department of Medicine (S.C., M.B., A.P.T., A.V.M.), David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California 90095; and Department of Physiology and Biomedical Engineering (A.V.M.), Mayo Clinic School of Medicine, Mayo Clinic Rochester, Minnesota 55905
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Jung M, Lee J, Seo HY, Lim JS, Kim EK. Cathepsin inhibition-induced lysosomal dysfunction enhances pancreatic beta-cell apoptosis in high glucose. PLoS One 2015; 10:e0116972. [PMID: 25625842 PMCID: PMC4308077 DOI: 10.1371/journal.pone.0116972] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2014] [Accepted: 12/17/2014] [Indexed: 12/19/2022] Open
Abstract
Autophagy is a lysosomal degradative pathway that plays an important role in maintaining cellular homeostasis. We previously showed that the inhibition of autophagy causes pancreatic β-cell apoptosis, suggesting that autophagy is a protective mechanism for the survival of pancreatic β-cells. The current study demonstrates that treatment with inhibitors and knockdown of the lysosomal cysteine proteases such as cathepsins B and L impair autophagy, enhancing the caspase-dependent apoptosis of INS-1 cells and islets upon exposure to high concentration of glucose. Interestingly, treatment with cathepsin B and L inhibitors prevented the proteolytic processing of cathepsins B, D and L, as evidenced by gradual accumulation of the respective pro-forms. Of note, inhibition of aspartic cathepsins had no effect on autophagy and cell viability, suggesting the selective role of cathepsins B and L in the regulation of β-cell autophagy and apoptosis. Lysosomal localization of accumulated pro-cathepsins in the presence of cathepsin B and L inhibitors was verified via immunocytochemistry and lysosomal fractionation. Lysotracker staining indicated that cathepsin B and L inhibitors led to the formation of severely enlarged lysosomes in a time-dependent manner. The abnormal accumulation of pro-cathepsins following treatment with inhibitors of cathepsins B and L suppressed normal lysosomal degradation and the processing of lysosomal enzymes, leading to lysosomal dysfunction. Collectively, our findings suggest that cathepsin defects following the inhibition of cathepsin B and L result in lysosomal dysfunction and consequent cell death in pancreatic β-cells.
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Affiliation(s)
- Minjeong Jung
- Department of Brain Science, Daegu Gyeongbuk Institute of Science & Technology, Daegu, Korea
| | - Jaemeun Lee
- Department of Brain Science, Daegu Gyeongbuk Institute of Science & Technology, Daegu, Korea
| | - Hye-Young Seo
- Department of Brain Science, Daegu Gyeongbuk Institute of Science & Technology, Daegu, Korea
| | - Ji Sun Lim
- Department of Brain Science, Daegu Gyeongbuk Institute of Science & Technology, Daegu, Korea
| | - Eun-Kyoung Kim
- Department of Brain Science, Daegu Gyeongbuk Institute of Science & Technology, Daegu, Korea; Neurometabolomics Research Center, Daegu Gyeongbuk Institute of Science & Technology, Daegu, Korea
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48
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Kuhn H, Banthiya S, van Leyen K. Mammalian lipoxygenases and their biological relevance. Biochim Biophys Acta Mol Cell Biol Lipids 2014; 1851:308-30. [PMID: 25316652 DOI: 10.1016/j.bbalip.2014.10.002] [Citation(s) in RCA: 413] [Impact Index Per Article: 41.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 09/30/2014] [Accepted: 10/03/2014] [Indexed: 02/07/2023]
Abstract
Lipoxygenases (LOXs) form a heterogeneous class of lipid peroxidizing enzymes, which have been implicated not only in cell proliferation and differentiation but also in the pathogenesis of various diseases with major public health relevance. As other fatty acid dioxygenases LOXs oxidize polyunsaturated fatty acids to their corresponding hydroperoxy derivatives, which are further transformed to bioactive lipid mediators (eicosanoids and related substances). On the other hand, lipoxygenases are key players in the regulation of the cellular redox homeostasis, which is an important element in gene expression regulation. Although the first mammalian lipoxygenases were discovered 40 years ago and although the enzymes have been well characterized with respect to their structural and functional properties the biological roles of the different lipoxygenase isoforms are not completely understood. This review is aimed at summarizing the current knowledge on the physiological roles of different mammalian LOX-isoforms and their patho-physiological function in inflammatory, metabolic, hyperproliferative, neurodegenerative and infectious disorders. This article is part of a Special Issue entitled "Oxygenated metabolism of PUFA: analysis and biological relevance".
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Affiliation(s)
- Hartmut Kuhn
- Institute of Biochemistry, University Medicine Berlin - Charite, Chariteplatz 1, CCO-Building, Virchowweg 6, D-10117 Berlin, Germany.
| | - Swathi Banthiya
- Institute of Biochemistry, University Medicine Berlin - Charite, Chariteplatz 1, CCO-Building, Virchowweg 6, D-10117 Berlin, Germany
| | - Klaus van Leyen
- Neuroprotection Research Laboratory, Department of Radiology, Massachusetts Genrel Hospital and Harvard Medical School, Charlestown, MA, USA
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12-lipoxygenase promotes obesity-induced oxidative stress in pancreatic islets. Mol Cell Biol 2014; 34:3735-45. [PMID: 25071151 DOI: 10.1128/mcb.00157-14] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
High-fat diets lead to obesity, inflammation, and dysglycemia. 12-Lipoxygenase (12-LO) is activated by high-fat diets and catalyzes the oxygenation of cellular arachidonic acid to form proinflammatory intermediates. We hypothesized that 12-LO in the pancreatic islet is sufficient to cause dysglycemia in the setting of high-fat feeding. To test this, we generated pancreas-specific 12-LO knockout mice and studied their metabolic and molecular adaptations to high-fat diets. Whereas knockout mice and control littermates displayed identical weight gain, body fat distribution, and macrophage infiltration into fat, knockout mice exhibited greater adaptive islet hyperplasia, improved insulin secretion, and complete protection from dysglycemia. At the molecular level, 12-LO deletion resulted in increases in islet antioxidant enzymes Sod1 and Gpx1 in response to high-fat feeding. The absence or inhibition of 12-LO led to increases in nuclear Nrf2, a transcription factor responsible for activation of genes encoding antioxidant enzymes. Our data reveal a novel pathway in which islet 12-LO suppresses antioxidant enzymes and prevents the adaptive islet responses in the setting of high-fat diets.
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50
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Novelli M, Canistro D, Martano M, Funel N, Sapone A, Melega S, Masini M, De Tata V, Pippa A, Vecoli C, Campani D, De Siena R, Soleti A, Paolini M, Masiello P. Anti-diabetic properties of a non-conventional radical scavenger, as compared to pioglitazone and exendin-4, in streptozotocin-nicotinamide diabetic mice. Eur J Pharmacol 2014; 729:37-44. [PMID: 24530416 DOI: 10.1016/j.ejphar.2014.01.071] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2013] [Revised: 01/22/2014] [Accepted: 01/24/2014] [Indexed: 12/13/2022]
Abstract
We previously showed that the innovative radical scavenger bis(1-hydroxy-2,2,6,6-tetramethyl-4-piperidinyl)-decandioate (IAC) improves metabolic dysfunctions in a diabetic mouse model. Here, we compared the in vivo effects of IAC with those of the anti-diabetic drugs pioglitazone (PIO) and exendin-4 (EX-4). Diabetes was induced in C57Bl/6J mice by streptozotocin and nicotinamide administration. Paralleled by healthy controls, diabetic animals (D) were randomly assigned to four groups and treated daily for 7 consecutive weeks: D+saline, ip; D+IAC 30mg/kgb.w., ip; D+PIO 10mg/kgb.w. per os; and D+EX-4, 50μg/kgb.w., ip. Our results show that IAC reduced basal hyperglycemia and improved glucose tolerance better than PIO or EX-4. Interestingly, in the heart of diabetic mice, IAC treatment normalized the increased levels of GSSG/GSH ratio and thiobarbituric acid reactive substances, indexes of oxidative stress and damage, while PIO and EX-4 were less effective. As supported by immunohistochemical data, IAC markedly prevented diabetic islet β-cell reduced density, differently from PIO and EX-4 that had only a moderate effect. Interestingly, in diabetic animals, IAC treatment enhanced the activity of pancreatic-duodenal homeobox 1 (PDX-1), an oxidative stress-sensitive transcription factor essential for maintenance of β-cell function, as evaluated by quantification of its nuclear immunostaining, whereas PIO or EX-4 treatments did not. Altogether, these observations support the improvement of the general redox balance and β-cell function induced by IAC treatment in streptozotocin-nicotinamide diabetic mice. Furthermore, in this model, the correction of diabetic alterations was better obtained by treatment with the radical scavenger IAC than with pioglitazone or exendin-4.
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Affiliation(s)
- Michela Novelli
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma 55, 56126 Pisa, Italy
| | - Donatella Canistro
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy
| | | | - Niccola Funel
- Department of Surgical, Medical, Molecular, and Critical Area Pathology, University of Pisa, Via Savi 10, 56126 Pisa, Italy
| | - Andrea Sapone
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy
| | - Simone Melega
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy
| | - Matilde Masini
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma 55, 56126 Pisa, Italy
| | - Vincenzo De Tata
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma 55, 56126 Pisa, Italy
| | - Anna Pippa
- Institute of Clinical Physiology, CNR, Via Moruzzi 1, 56124 Pisa, Italy
| | - Cecilia Vecoli
- Institute of Clinical Physiology, CNR, Via Moruzzi 1, 56124 Pisa, Italy
| | - Daniela Campani
- Department of Surgical, Medical, Molecular, and Critical Area Pathology, University of Pisa, Via Savi 10, 56126 Pisa, Italy
| | | | | | - Moreno Paolini
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy
| | - Pellegrino Masiello
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma 55, 56126 Pisa, Italy.
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