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Hawes EM, Rahim M, Haratipour Z, Orun AR, O'Rourke ML, Oeser JK, Kim K, Claxton DP, Blind RD, Young JD, O'Brien RM. Biochemical and metabolic characterization of a G6PC2 inhibitor. Biochimie 2024; 222:109-122. [PMID: 38431189 DOI: 10.1016/j.biochi.2024.02.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 02/28/2024] [Accepted: 02/29/2024] [Indexed: 03/05/2024]
Abstract
Three glucose-6-phosphatase catalytic subunits, that hydrolyze glucose-6-phosphate (G6P) to glucose and inorganic phosphate, have been identified, designated G6PC1-3, but only G6PC1 and G6PC2 have been implicated in the regulation of fasting blood glucose (FBG). Elevated FBG has been associated with multiple adverse clinical outcomes, including increased risk for type 2 diabetes and various cancers. Therefore, G6PC1 and G6PC2 inhibitors that lower FBG may be of prophylactic value for the prevention of multiple conditions. The studies described here characterize a G6PC2 inhibitor, designated VU0945627, previously identified as Compound 3. We show that VU0945627 preferentially inhibits human G6PC2 versus human G6PC1 but activates human G6PC3. VU0945627 is a mixed G6PC2 inhibitor, increasing the Km but reducing the Vmax for G6P hydrolysis. PyRx virtual docking to an AlphaFold2-derived G6PC2 structural model suggests VU0945627 binds two sites in human G6PC2. Mutation of residues in these sites reduces the inhibitory effect of VU0945627. VU0945627 does not inhibit mouse G6PC2 despite its 84% sequence identity with human G6PC2. Mutagenesis studies suggest this lack of inhibition of mouse G6PC2 is due, in part, to a change in residue 318 from histidine in human G6PC2 to proline in mouse G6PC2. Surprisingly, VU0945627 still inhibited glucose cycling in the mouse islet-derived βTC-3 cell line. Studies using intact mouse liver microsomes and PyRx docking suggest that this observation can be explained by an ability of VU0945627 to also inhibit the G6P transporter SLC37A4. These data will inform future computational modeling studies designed to identify G6PC isoform-specific inhibitors.
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Affiliation(s)
- Emily M Hawes
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA
| | - Mohsin Rahim
- Department of Chemical and Biomolecular Engineering, Vanderbilt School of Engineering, Nashville, TN, 37232, USA
| | - Zeinab Haratipour
- Austin Peay State University, 601 College St, Clarksville, TN 37044, USA; Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA
| | - Abigail R Orun
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA
| | - Margaret L O'Rourke
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA
| | - James K Oeser
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA
| | - Kwangho Kim
- Department of Chemistry, Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN, 37232, USA
| | - Derek P Claxton
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA
| | - Ray D Blind
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA
| | - Jamey D Young
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA; Department of Chemical and Biomolecular Engineering, Vanderbilt School of Engineering, Nashville, TN, 37232, USA
| | - Richard M O'Brien
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA.
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2
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Ziari N, Hellerstein M. Measurement of gluconeogenesis by 2H 2O labeling and mass isotopomer distribution analysis. J Biol Chem 2023; 299:105206. [PMID: 37660907 PMCID: PMC10539955 DOI: 10.1016/j.jbc.2023.105206] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 08/21/2023] [Accepted: 08/23/2023] [Indexed: 09/05/2023] Open
Abstract
The gluconeogenesis pathway, which converts nonsugar molecules into glucose, is critical for maintaining glucose homeostasis. Techniques that measure flux through this pathway are invaluable for studying metabolic diseases such as diabetes that are associated with dysregulation of this pathway. We introduce a new method that measures fractional gluconeogenesis by heavy water labeling and gas chromatographic-mass spectrometric analysis. This technique circumvents cumbersome benchwork or inference of positionality from mass spectra. The enrichment and pattern of deuterium label on glucose is quantified by use of mass isotopomer distribution analysis, which informs on how much of glucose-6-phosphate-derived glucose comes from the gluconeogenesis (GNG) pathway. We use an in vivo model of the GNG pathway that is based on previously published models but offers a new approach to calculating GNG pathway and subpathway contributions using combinatorial probabilities. We demonstrated that this method accurately quantifies fractional GNG through experiments that perturb flux through the pathway and by probing analytical sensitivity. While this method was developed in mice, the results suggest that it is translatable to humans in a clinical setting.
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Affiliation(s)
- Naveed Ziari
- Department of Nutritional Sciences & Toxicology, University of California, Berkeley, California, USA
| | - Marc Hellerstein
- Department of Nutritional Sciences & Toxicology, University of California, Berkeley, California, USA.
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3
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Lee RA, Chang M, Yiv N, Tsay A, Tian S, Li D, Poulard C, Stallcup MR, Pufall MA, Wang JC. Transcriptional coactivation by EHMT2 restricts glucocorticoid-induced insulin resistance in a study with male mice. Nat Commun 2023; 14:3143. [PMID: 37253782 PMCID: PMC10229547 DOI: 10.1038/s41467-023-38584-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 05/09/2023] [Indexed: 06/01/2023] Open
Abstract
The classical dogma of glucocorticoid-induced insulin resistance is that it is caused by the transcriptional activation of hepatic gluconeogenic and insulin resistance genes by the glucocorticoid receptor (GR). Here, we find that glucocorticoids also stimulate the expression of insulin-sensitizing genes, such as Irs2. The transcriptional coregulator EHMT2 can serve as a transcriptional coactivator or a corepressor. Using male mice that have a defective EHMT2 coactivation function specifically, we show that glucocorticoid-induced Irs2 transcription is dependent on liver EHMT2's coactivation function and that IRS2 play a key role in mediating the limitation of glucocorticoid-induced insulin resistance by EHMT2's coactivation. Overall, we propose a model in which glucocorticoid-regulated insulin sensitivity is determined by the balance between glucocorticoid-modulated insulin resistance and insulin sensitizing genes, in which EHMT2 coactivation is specifically involved in the latter process.
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Affiliation(s)
- Rebecca A Lee
- Endocrinology Graduate Program, University of California Berkeley, Berkeley, CA, 94720, USA
- Department of Nutritional Sciences & Toxicology, University of California Berkeley, Berkeley, CA, 94720, USA
| | - Maggie Chang
- Endocrinology Graduate Program, University of California Berkeley, Berkeley, CA, 94720, USA
- Department of Nutritional Sciences & Toxicology, University of California Berkeley, Berkeley, CA, 94720, USA
| | - Nicholas Yiv
- Department of Nutritional Sciences & Toxicology, University of California Berkeley, Berkeley, CA, 94720, USA
- Metabolic Biology Graduate Program, University of California Berkeley, Berkeley, CA, 94720, USA
| | - Ariel Tsay
- Department of Nutritional Sciences & Toxicology, University of California Berkeley, Berkeley, CA, 94720, USA
- Metabolic Biology Graduate Program, University of California Berkeley, Berkeley, CA, 94720, USA
| | - Sharon Tian
- Department of Nutritional Sciences & Toxicology, University of California Berkeley, Berkeley, CA, 94720, USA
| | - Danielle Li
- Department of Nutritional Sciences & Toxicology, University of California Berkeley, Berkeley, CA, 94720, USA
| | - Coralie Poulard
- Inserm U1052, Centre de Recherche en Cancérologie de Lyon, 28 Rue Laennec, 69000, Lyon, France
| | - Michael R Stallcup
- Department of Biochemistry and Molecular Medicine, University of Southern California, Los Angeles, CA, 90089, USA
| | - Miles A Pufall
- Department of Biochemistry and Molecular Biology, University of Iowa Carver College of Medicine, Iowa City, IA, 52242, USA
| | - Jen-Chywan Wang
- Endocrinology Graduate Program, University of California Berkeley, Berkeley, CA, 94720, USA.
- Department of Nutritional Sciences & Toxicology, University of California Berkeley, Berkeley, CA, 94720, USA.
- Metabolic Biology Graduate Program, University of California Berkeley, Berkeley, CA, 94720, USA.
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4
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Overway EM, Bosma KJ, Claxton DP, Oeser JK, Singh K, Breidenbach LB, Mchaourab HS, Davis LK, O'Brien RM. Nonsynonymous single-nucleotide polymorphisms in the G6PC2 gene affect protein expression, enzyme activity, and fasting blood glucose. J Biol Chem 2022; 298:101534. [PMID: 34954144 PMCID: PMC8800118 DOI: 10.1016/j.jbc.2021.101534] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 12/16/2021] [Accepted: 12/17/2021] [Indexed: 12/30/2022] Open
Abstract
G6PC2 encodes a glucose-6-phosphatase (G6Pase) catalytic subunit that modulates the sensitivity of insulin secretion to glucose and thereby regulates fasting blood glucose (FBG). A common single-nucleotide polymorphism (SNP) in G6PC2, rs560887 is an important determinant of human FBG variability. This SNP has a subtle effect on G6PC2 RNA splicing, which raises the question as to whether nonsynonymous SNPs with a major impact on G6PC2 stability or enzyme activity might have a broader disease/metabolic impact. Previous attempts to characterize such SNPs were limited by the very low inherent G6Pase activity and expression of G6PC2 protein in islet-derived cell lines. In this study, we describe the use of a plasmid vector that confers high G6PC2 protein expression in islet cells, allowing for a functional analysis of 22 nonsynonymous G6PC2 SNPs, 19 of which alter amino acids that are conserved in mouse G6PC2 and the human and mouse variants of the related G6PC1 isoform. We show that 16 of these SNPs markedly impair G6PC2 protein expression (>50% decrease). These SNPs have variable effects on the stability of human and mouse G6PC1, despite the high sequence homology between these isoforms. Four of the remaining six SNPs impaired G6PC2 enzyme activity. Electronic health record-derived phenotype analyses showed an association between high-impact SNPs and FBG, but not other diseases/metabolites. While homozygous G6pc2 deletion in mice increases the risk of hypoglycemia, these human data reveal no evidence that the beneficial use of partial G6PC2 inhibitors to lower FBG would be associated with unintended negative consequences.
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Affiliation(s)
- Emily M Overway
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Karin J Bosma
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Derek P Claxton
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - James K Oeser
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Kritika Singh
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Lindsay B Breidenbach
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Hassane S Mchaourab
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Lea K Davis
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA; Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Richard M O'Brien
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.
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Dexamethasone Administration in Mice Leads to Less Body Weight Gain over Time, Lower Serum Glucose, and Higher Insulin Levels Independently of NRF2. Antioxidants (Basel) 2021; 11:antiox11010004. [PMID: 35052508 PMCID: PMC8773000 DOI: 10.3390/antiox11010004] [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: 12/06/2021] [Revised: 12/17/2021] [Accepted: 12/19/2021] [Indexed: 12/17/2022] Open
Abstract
Glucocorticoids are used widely on a long-term basis in autoimmune and inflammatory diseases. Their adverse effects include the development of hyperglycemia and osteoporosis, whose molecular mechanisms have been only partially studied in preclinical models. Both these glucocorticoid-induced pathologies have been shown to be mediated at least in part by oxidative stress. The transcription factor nuclear erythroid factor 2-like 2 (NRF2) is a central regulator of antioxidant and cytoprotective responses. Thus, we hypothesized that NRF2 may play a role in glucocorticoid-induced metabolic disease and osteoporosis. To this end, WT and Nrf2 knockout (Nrf2KO) mice of both genders were treated with 2 mg/kg dexamethasone or vehicle 3 times per week for 13 weeks. Dexamethasone treatment led to less weight gain during the treatment period without affecting food consumption, as well as to lower glucose levels and high insulin levels compared to vehicle-treated mice. Dexamethasone also reduced cortical bone volume and density. All these effects of dexamethasone were similar between male and female mice, as well as between WT and Nrf2KO mice. Hepatic NRF2 signaling and gluconeogenic gene expression were not affected by dexamethasone. A 2-day dexamethasone treatment was also sufficient to increase insulin levels without affecting body weight and glucose levels. Hence, dexamethasone induces hyperinsulinemia, which potentially leads to decreased glucose levels, as well as osteoporosis, both independently of NRF2.
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Zhao Z, Xu X, Jiang H, Foster KW, Jia Z, Wei X, Chen N, Goldring SR, Crow MK, Wang D. Preclinical Dose-Escalation Study of ZSJ-0228, a Polymeric Dexamethasone Prodrug, in the Treatment of Murine Lupus Nephritis. Mol Pharm 2021; 18:4188-4197. [PMID: 34569234 DOI: 10.1021/acs.molpharmaceut.1c00567] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Glucocorticoids (GCs) are widely used in the clinical management of lupus nephritis (LN). Their long-term use, however, is associated with the risk of significant systemic side effects. We have developed a poly(ethylene glycol) (PEG)-based dexamethasone (Dex) prodrug (i.e., ZSJ-0228) and in a previous study, demonstrated its potential therapeutic efficacy in mice with established LN, while avoiding systemic GC-associated toxicity. In the present study, we have employed a dose-escalation design to establish the optimal dose-response relationships for ZSJ-0228 in treating LN and further investigated the safety of ZSJ-0228 in lupus-prone NZB/W F1 mice with established nephritis. ZSJ-0228 was intravenously (i.v.) administered monthly at four levels: 0.5 (L1), 1.0 (L2), 3.0 (L3), and 8.0 (L4) mg/kg/day Dex equivalent. For controls, mice were treated with i.v. saline every 4 weeks. In addition, a group of mice received intraperitoneal injections (i.p.) of Dex every day or i.v. injections of Dex every four weeks. Treatment of mice with LN with ZSJ-0228 dosed at L1 resulted in the resolution of proteinuria in 14% of the mice. Mice treated with ZSJ-0228 dosed at L2 and L3 levels resulted in the resolution of proteinuria in ∼60% of the mice in both groups. Treatment with ZSJ-0228 dosed at L4 resulted in the resolution of proteinuria in 30% of the mice. The reduction and/or resolution of the proteinuria, improvement in renal histological scores, and survival data indicate that the most effective dose range for ZSJ-0228 in treating LN in NZB/W F1 mice is between 1.0 and 3.0 mg/kg/day Dex equivalent. Typical GC-associated side effects (e.g., osteopenia, adrenal glands atrophy, etc.) were not observed in any of the ZSJ-0228 treatment groups, confirming its excellent safety profile.
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Affiliation(s)
- Zhifeng Zhao
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska 68198-6125, United States
| | - Xiaoke Xu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska 68198-6125, United States
| | - Haochen Jiang
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska 68198-6125, United States
| | - Kirk W Foster
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, Nebraska 68198-5900, United States
| | - Zhenshan Jia
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska 68198-6125, United States
| | - Xin Wei
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska 68198-6125, United States
| | - Ningrong Chen
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska 68198-6125, United States
| | - Steven R Goldring
- Hospital for Special Surgery, New York, New York 10021, United States
| | - Mary K Crow
- Hospital for Special Surgery, New York, New York 10021, United States
| | - Dong Wang
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska 68198-6125, United States
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7
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Mining novel cell glycolysis related gene markers that can predict the survival of colon adenocarcinoma patients. Biosci Rep 2021; 40:225964. [PMID: 32744303 PMCID: PMC7426632 DOI: 10.1042/bsr20201427] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 07/27/2020] [Accepted: 07/31/2020] [Indexed: 12/20/2022] Open
Abstract
Colon adenocarcinoma (COAD) is a malignant gastrointestinal tumor, often occurring in the left colon, which is regulated by glycolysis-related processes. In past studies, multiple genes that influence the prognosis for survival have been discovered through bioinformatics analysis. However, the prediction of disease prognosis using a single gene is not an accurate method. In the present study, a mechanistic model was established to achieve better prediction for the prognosis of COAD. COAD-related data downloaded from The Cancer Genome Atlas (TCGA) were correlated with the glycolysis process using gene set enrichment analysis (GSEA) to determine the glycolysis-related genes that regulate COAD. Using COX regression analysis, glycolysis-related genes associated with the prognosis of COAD were identified, and the genes screened to establish a predictive model. The risk scores of this model were correlated with relevant clinical data to obtain a connection diagram between the model and survival rate, tumor characteristic data, etc. Finally, genes in the model were correlated with cells in the tumor microenvironment, finding that they affected specific immune cells in the model. Seven genes related to glycolysis were identified (PPARGC1A, DLAT, 6PC2, P4HA1, STC2, ANKZF1, and GPC1), which affect the prognosis of patients with COAD and constitute the model for prediction of survival of COAD patients.
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8
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Tahbaz M, Yoshihara E. Immune Protection of Stem Cell-Derived Islet Cell Therapy for Treating Diabetes. Front Endocrinol (Lausanne) 2021; 12:716625. [PMID: 34447354 PMCID: PMC8382875 DOI: 10.3389/fendo.2021.716625] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 07/19/2021] [Indexed: 12/14/2022] Open
Abstract
Insulin injection is currently the main therapy for type 1 diabetes (T1D) or late stage of severe type 2 diabetes (T2D). Human pancreatic islet transplantation confers a significant improvement in glycemic control and prevents life-threatening severe hypoglycemia in T1D patients. However, the shortage of cadaveric human islets limits their therapeutic potential. In addition, chronic immunosuppression, which is required to avoid rejection of transplanted islets, is associated with severe complications, such as an increased risk of malignancies and infections. Thus, there is a significant need for novel approaches to the large-scale generation of functional human islets protected from autoimmune rejection in order to ensure durable graft acceptance without immunosuppression. An important step in addressing this need is to strengthen our understanding of transplant immune tolerance mechanisms for both graft rejection and autoimmune rejection. Engineering of functional human pancreatic islets that can avoid attacks from host immune cells would provide an alternative safe resource for transplantation therapy. Human pluripotent stem cells (hPSCs) offer a potentially limitless supply of cells because of their self-renewal ability and pluripotency. Therefore, studying immune tolerance induction in hPSC-derived human pancreatic islets will directly contribute toward the goal of generating a functional cure for insulin-dependent diabetes. In this review, we will discuss the current progress in the immune protection of stem cell-derived islet cell therapy for treating diabetes.
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Affiliation(s)
- Meghan Tahbaz
- Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, CA, United States
| | - Eiji Yoshihara
- Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, CA, United States
- David Geffen School of Medicine at University of California, Los Angeles, CA, United States
- *Correspondence: Eiji Yoshihara,
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9
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Bosma KJ, Rahim M, Oeser JK, McGuinness OP, Young JD, O'Brien RM. G6PC2 confers protection against hypoglycemia upon ketogenic diet feeding and prolonged fasting. Mol Metab 2020; 41:101043. [PMID: 32569842 PMCID: PMC7369601 DOI: 10.1016/j.molmet.2020.101043] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 05/26/2020] [Accepted: 06/16/2020] [Indexed: 12/14/2022] Open
Abstract
Objective G6PC2 is predominantly expressed in pancreatic islet beta cells. G6PC2 hydrolyzes glucose-6-phosphate to glucose and inorganic phosphate, thereby creating a futile substrate cycle that opposes the action of glucokinase. This substrate cycle determines the sensitivity of glucose-stimulated insulin secretion to glucose and hence regulates fasting blood glucose (FBG) but not fasting plasma insulin (FPI) levels. Our objective was to explore the physiological benefit this cycle confers. Methods We investigated the response of wild type (WT) and G6pc2 knockout (KO) mice to changes in nutrition. Results Pancreatic G6pc2 expression was little changed by ketogenic diet feeding but was inhibited by 24 hr fasting and strongly induced by high fat feeding. When challenged with either a ketogenic diet or 24 hr fasting, blood glucose fell to 70 mg/dl or less in G6pc2 KO but not WT mice, suggesting that G6PC2 may have evolved, in part, to prevent hypoglycemia. Prolonged ketogenic diet feeding reduced the effect of G6pc2 deletion on FBG. The hyperglycemia associated with high fat feeding was partially blunted in G6pc2 KO mice, suggesting that under these conditions the presence of G6PC2 is detrimental. As expected, FPI changed but did not differ between WT and KO mice in response to fasting, ketogenic and high fat feeding. Conclusions Since elevated FBG levels are associated with increased risk for cardiovascular-associated mortality (CAM), these studies suggest that, while G6PC2 inhibitors would be useful for lowering FBG and the risk of CAM, partial inhibition will be important to avoid the risk of hypoglycemia. G6pc2 deletion lowers fasting blood glucose (FBG) in chow and high fat fed mice. Elevated FBG increases the risk of cardiovascular-associated mortality (CAM). G6pc2 deletion results in hypoglycemia in mice on a ketogenic diet. G6pc2 deletion results in hypoglycemia in mice following prolonged fasting. G6PC2 inhibitors may prevent CAM but increase risk of hypoglycemia.
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Affiliation(s)
- Karin J Bosma
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Mohsin Rahim
- Department of Chemical and Biomolecular Engineering, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA
| | - James K Oeser
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Owen P McGuinness
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Jamey D Young
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Chemical and Biomolecular Engineering, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA
| | - Richard M O'Brien
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
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10
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Guo S, Guo X, Zhang H, Zhang X, Li Z. The Effect of Diacerein on Type 2 Diabetic Mellitus: A Systematic Review and Meta-Analysis of Randomized Controlled Trials with Trial Sequential Analysis. J Diabetes Res 2020; 2020:2593792. [PMID: 32104712 PMCID: PMC7035565 DOI: 10.1155/2020/2593792] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 01/02/2020] [Indexed: 02/07/2023] Open
Abstract
AIMS To figure out the effect of diacerein supplementation on type 2 diabetes mellitus (T2DM). METHODS An electronic search was processed on Pubmed, Embase, and Cochrane library for randomized controlled trials (RCTs) comparing the efficacy of diacerein with placebo on T2DM. The primary outcome was fasting blood glucose (FBG). Trial sequential analysis (TSA) was used to test the reliability of this pooled outcome. Secondary outcomes were glycosylated hemoglobin A1c (HbA1c), body mass index (BMI), lipid profiles, hematological indexes including hematocrit and platelet count, and systematic inflammatory level expressed as a C-reactive protein (CRP) level. Safety outcome was the rate of complications. The difference in continuous data was measured by mean difference (MD) and 95% confidence interval (CI), while the difference of dichotomous data was calculated by relative risk (RR) and 95% CI. A two-tailed P < 0.05 was regarded as statistically significant. RESULTS Five RCTs with 278 participants were included. Compared with control, diacerein provided significant improvement on FBG (MD -0.52; 95% CI (-0.89~-0.14); P < 0.05 was regarded as statistically significant. P < 0.05 was regarded as statistically significant. P < 0.05 was regarded as statistically significant. P < 0.05 was regarded as statistically significant. P < 0.05 was regarded as statistically significant. CONCLUSION Based on the current analysis, diacerein as an add-on treatment provided better glycemic control for T2DM but this benefit requires more verification. Compared with control, additional diacerein also lowered body weight and CRP level in T2DM, but increased the rate of gastrointestinal syndromes.
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Affiliation(s)
- Shizhe Guo
- Internal Medicine Base, Yangpu Hospital, Tongji University School of Medicine, Shanghai 200090, China
| | - Xianshan Guo
- Department of Endocrinology, Xinxiang Central Hospital, Xinxiang, Henan 453000, China
| | - Hongya Zhang
- Central Laboratory, Yang Pu District Center of Disease Control and Prevention, Shanghai 200090, China
| | - Xuan'e Zhang
- Department of Endocrinology, Yangpu Hospital, Tongji University School of Medicine, Shanghai 200090, China
| | - Zhen Li
- Department of General Surgery, Yangpu Hospital, Tongji University School of Medicine, Shanghai 200090, China
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11
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Courty E, Besseiche A, Do TTH, Liboz A, Aguid FM, Quilichini E, Buscato M, Gourdy P, Gautier JF, Riveline JP, Haumaitre C, Buyse M, Fève B, Guillemain G, Blondeau B. Adaptive β-Cell Neogenesis in the Adult Mouse in Response to Glucocorticoid-Induced Insulin Resistance. Diabetes 2019; 68:95-108. [PMID: 30327384 DOI: 10.2337/db17-1314] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 10/11/2018] [Indexed: 11/13/2022]
Abstract
Both type 1 and type 2 diabetes are characterized by deficient insulin secretion and decreased β-cell mass. Thus, regenerative strategies to increase β-cell mass need to be developed. To characterize mechanisms of β-cell plasticity, we studied a model of severe insulin resistance in the adult mouse and defined how β-cells adapt. Chronic corticosterone (CORT) treatment was given to adult mice and led to rapid insulin resistance and adaptive increased insulin secretion. Adaptive and massive increase of β-cell mass was observed during treatment up to 8 weeks. β-Cell mass increase was partially reversible upon treatment cessation and reinduced upon subsequent treatment. β-Cell neogenesis was suggested by an increased number of islets, mainly close to ducts, and increased Sox9 and Ngn3 mRNA levels in islets, but lineage-tracing experiments revealed that neoformed β-cells did not derive from Sox9- or Ngn3-expressing cells. CORT treatment after β-cell depletion partially restored β-cells. Finally, β-cell neogenesis was shown to be indirectly stimulated by CORT because serum from CORT-treated mice increased β-cell differentiation in in vitro cultures of pancreatic buds. Altogether, the results present a novel model of β-cell neogenesis in the adult mouse and identify the presence of neogenic factors in the serum of CORT-treated mice.
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Affiliation(s)
- Emilie Courty
- Sorbonne Université, INSERM, Saint-Antoine Research Center, Paris, France
- Hospitalo-Universitary Institute, ICAN, Paris, France
| | - Adrien Besseiche
- Sorbonne Université, INSERM, Centre de Recherche des Cordeliers, Paris, France
| | - Thi Thu Huong Do
- Sorbonne Université, INSERM, Saint-Antoine Research Center, Paris, France
- Hospitalo-Universitary Institute, ICAN, Paris, France
| | - Alexandrine Liboz
- Sorbonne Université, INSERM, Saint-Antoine Research Center, Paris, France
- Hospitalo-Universitary Institute, ICAN, Paris, France
| | | | - Evans Quilichini
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, Paris, France
| | - Melissa Buscato
- Institute of Metabolic and Cardiovascular Diseases, UMR1048, INSERM, UPS, Université de Toulouse, Toulouse, France
| | - Pierre Gourdy
- Institute of Metabolic and Cardiovascular Diseases, UMR1048, INSERM, UPS, Université de Toulouse, Toulouse, France
- Service de Diabétologie, CHU de Toulouse, Toulouse, France
| | - Jean-François Gautier
- Sorbonne Université, INSERM, Centre de Recherche des Cordeliers, Paris, France
- Lariboisière Hospital, Assistance Publique-Hôpitaux de Paris, Department of Diabetes and Endocrinology, University Paris-Diderot 7, Sorbonne Paris Cité, Paris, France
| | - Jean-Pierre Riveline
- Sorbonne Université, INSERM, Centre de Recherche des Cordeliers, Paris, France
- Lariboisière Hospital, Assistance Publique-Hôpitaux de Paris, Department of Diabetes and Endocrinology, University Paris-Diderot 7, Sorbonne Paris Cité, Paris, France
| | - Cécile Haumaitre
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, Paris, France
| | - Marion Buyse
- Sorbonne Université, INSERM, Saint-Antoine Research Center, Paris, France
- Hospitalo-Universitary Institute, ICAN, Paris, France
- Université Paris-Sud, EA 4123, Chatenay-Malabry, France
- Department of Pharmacy, Saint-Antoine Hospital, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Bruno Fève
- Sorbonne Université, INSERM, Saint-Antoine Research Center, Paris, France
- Hospitalo-Universitary Institute, ICAN, Paris, France
- Department of Endocrinology, Saint-Antoine Hospital, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Ghislaine Guillemain
- Sorbonne Université, INSERM, Saint-Antoine Research Center, Paris, France
- Hospitalo-Universitary Institute, ICAN, Paris, France
| | - Bertrand Blondeau
- Sorbonne Université, INSERM, Saint-Antoine Research Center, Paris, France
- Hospitalo-Universitary Institute, ICAN, Paris, France
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Boortz KA, Syring KE, Pound LD, Mo H, Bastarache L, Oeser JK, McGuinness OP, Denny JC, O’Brien RM. Effects of G6pc2 deletion on body weight and cholesterol in mice. J Mol Endocrinol 2017; 58:127-139. [PMID: 28122818 PMCID: PMC5380368 DOI: 10.1530/jme-16-0202] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Accepted: 01/24/2017] [Indexed: 11/08/2022]
Abstract
Genome-wide association study (GWAS) data have linked the G6PC2 gene to variations in fasting blood glucose (FBG). G6PC2 encodes an islet-specific glucose-6-phosphatase catalytic subunit that forms a substrate cycle with the beta cell glucose sensor glucokinase. This cycle modulates the glucose sensitivity of insulin secretion and hence FBG. GWAS data have not linked G6PC2 to variations in body weight but we previously reported that female C57BL/6J G6pc2-knockout (KO) mice were lighter than wild-type littermates on both a chow and high-fat diet. The purpose of this study was to compare the effects of G6pc2 deletion on FBG and body weight in both chow-fed and high-fat-fed mice on two other genetic backgrounds. FBG was reduced in G6pc2 KO mice largely independent of gender, genetic background or diet. In contrast, the effect of G6pc2 deletion on body weight was markedly influenced by these variables. Deletion of G6pc2 conferred a marked protection against diet-induced obesity in male mixed genetic background mice, whereas in 129SvEv mice deletion of G6pc2 had no effect on body weight. G6pc2 deletion also reduced plasma cholesterol levels in a manner dependent on gender, genetic background and diet. An association between G6PC2 and plasma cholesterol was also observed in humans through electronic health record-derived phenotype analyses. These observations suggest that the action of G6PC2 on FBG is largely independent of the influences of environment, modifier genes or epigenetic events, whereas the action of G6PC2 on body weight and cholesterol are influenced by unknown variables.
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Affiliation(s)
- Kayla A. Boortz
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232
| | - Kristen E. Syring
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232
| | - Lynley D. Pound
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232
| | - Huan Mo
- Department of Biomedical Informatics, Vanderbilt University School of Medicine, Nashville, TN 37232
| | - Lisa Bastarache
- Department of Biomedical Informatics, Vanderbilt University School of Medicine, Nashville, TN 37232
| | - James K. Oeser
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232
| | - Owen P. McGuinness
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232
| | - Joshua C. Denny
- Department of Biomedical Informatics, Vanderbilt University School of Medicine, Nashville, TN 37232
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232
| | - Richard M. O’Brien
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232
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