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Reay WR, Kiltschewskij DJ, Di Biase MA, Gerring ZF, Kundu K, Surendran P, Greco LA, Clarke ED, Collins CE, Mondul AM, Albanes D, Cairns MJ. Genetic influences on circulating retinol and its relationship to human health. Nat Commun 2024; 15:1490. [PMID: 38374065 PMCID: PMC10876955 DOI: 10.1038/s41467-024-45779-x] [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: 08/23/2023] [Accepted: 02/04/2024] [Indexed: 02/21/2024] Open
Abstract
Retinol is a fat-soluble vitamin that plays an essential role in many biological processes throughout the human lifespan. Here, we perform the largest genome-wide association study (GWAS) of retinol to date in up to 22,274 participants. We identify eight common variant loci associated with retinol, as well as a rare-variant signal. An integrative gene prioritisation pipeline supports novel retinol-associated genes outside of the main retinol transport complex (RBP4:TTR) related to lipid biology, energy homoeostasis, and endocrine signalling. Genetic proxies of circulating retinol were then used to estimate causal relationships with almost 20,000 clinical phenotypes via a phenome-wide Mendelian randomisation study (MR-pheWAS). The MR-pheWAS suggests that retinol may exert causal effects on inflammation, adiposity, ocular measures, the microbiome, and MRI-derived brain phenotypes, amongst several others. Conversely, circulating retinol may be causally influenced by factors including lipids and serum creatinine. Finally, we demonstrate how a retinol polygenic score could identify individuals more likely to fall outside of the normative range of circulating retinol for a given age. In summary, this study provides a comprehensive evaluation of the genetics of circulating retinol, as well as revealing traits which should be prioritised for further investigation with respect to retinol related therapies or nutritional intervention.
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Affiliation(s)
- William R Reay
- School of Biomedical Sciences and Pharmacy, The University of Newcastle, Callaghan, NSW, Australia.
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton, NSW, Australia.
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne, Melbourne, VIC, Australia.
| | - Dylan J Kiltschewskij
- School of Biomedical Sciences and Pharmacy, The University of Newcastle, Callaghan, NSW, Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton, NSW, Australia
| | - Maria A Di Biase
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne, Melbourne, VIC, Australia
- Department of Anatomy and Physiology, The University of Melbourne, Melbourne, VIC, Australia
- Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Zachary F Gerring
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Kousik Kundu
- Human Genetics, Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, UK
- Department of Haematology, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
| | - Praveen Surendran
- British Heart Foundation Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
- British Heart Foundation Centre of Research Excellence, School of Clinical Medicine, Addenbrooke's Hospital, University of Cambridge, Cambridge, UK
- Health Data Research UK, Wellcome Genome Campus and University of Cambridge, Hinxton, UK
| | - Laura A Greco
- School of Biomedical Sciences and Pharmacy, The University of Newcastle, Callaghan, NSW, Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton, NSW, Australia
| | - Erin D Clarke
- School of Health Sciences, The University of Newcastle, Callaghan, NSW, Australia
- Food and Nutrition Research Program, Hunter Medical Research Institute, New Lambton, NSW, Australia
| | - Clare E Collins
- School of Health Sciences, The University of Newcastle, Callaghan, NSW, Australia
- Food and Nutrition Research Program, Hunter Medical Research Institute, New Lambton, NSW, Australia
| | - Alison M Mondul
- Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI, USA
| | - Demetrius Albanes
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Department of Health and Human Services, Bethesda, MD, USA
| | - Murray J Cairns
- School of Biomedical Sciences and Pharmacy, The University of Newcastle, Callaghan, NSW, Australia.
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton, NSW, Australia.
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Paliwal A, Paliwal V, Jain S, Paliwal S, Sharma S. Current Insight on the Role of Glucokinase and Glucokinase Regulatory Protein in Diabetes. Mini Rev Med Chem 2024; 24:674-688. [PMID: 37612862 DOI: 10.2174/1389557523666230823151927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Revised: 06/19/2023] [Accepted: 07/13/2023] [Indexed: 08/25/2023]
Abstract
The glucokinase regulator (GCKR) gene encodes an inhibitor of the glucokinase enzyme (GCK), found only in hepatocytes and responsible for glucose metabolism. A common GCKR coding variation has been linked to various metabolic traits in genome-wide association studies. Rare GCKR polymorphisms influence GKRP activity, expression, and localization. Despite not being the cause, these variations are linked to hypertriglyceridemia. Because of their crystal structures, we now better understand the molecular interactions between GKRP and the GCK. Finally, small molecules that specifically bind to GKRP and decrease blood sugar levels in diabetic models have been identified. GCKR allelic spectrum changes affect lipid and glucose homeostasis. GKRP dysfunction has been linked to a variety of molecular causes, according to functional analysis. Numerous studies have shown that GKRP dysfunction is not the only cause of hypertriglyceridemia, implying that type 2 diabetes could be treated by activating liver-specific GCK via small molecule GKRP inhibition. The review emphasizes current discoveries concerning the characteristic roles of glucokinase and GKRP in hepatic glucose metabolism and diabetes. This information has influenced the growth of directed molecular therapies for diabetes, which has improved our understanding of lipid and glucose physiology.
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Affiliation(s)
- Ajita Paliwal
- Department of Pharmacy, Banasthali Vidyapith, Banasthali, Rajasthan, India
| | - Vartika Paliwal
- Department of Pharmacy, Banasthali Vidyapith, Banasthali, Rajasthan, India
| | - Smita Jain
- Department of Pharmacy, Banasthali Vidyapith, Banasthali, Rajasthan, India
| | - Sarvesh Paliwal
- Department of Pharmacy, Banasthali Vidyapith, Banasthali, Rajasthan, India
| | - Swapnil Sharma
- Department of Pharmacy, Banasthali Vidyapith, Banasthali, Rajasthan, India
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3
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Santoleri D, Lim HW, Emmett MJ, Stoute J, Gavin MJ, Sostre-Colón J, Uehara K, Welles JE, Liu KF, Lazar MA, Titchenell PM. Global-run on sequencing identifies Gm11967 as an Akt-dependent long noncoding RNA involved in insulin sensitivity. iScience 2022; 25:104410. [PMID: 35663017 PMCID: PMC9156944 DOI: 10.1016/j.isci.2022.104410] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 03/18/2022] [Accepted: 05/11/2022] [Indexed: 01/07/2023] Open
Abstract
The insulin responsive Akt and FoxO1 signaling axis is a key regulator of the hepatic transcriptional response to nutrient intake. Here, we used global run-on sequencing (GRO-seq) to measure the nascent transcriptional response to fasting and refeeding as well as define the specific role of hepatic Akt and FoxO1 signaling in mediating this response. We identified 599 feeding-regulated transcripts, as well as over 6,000 eRNAs, and mapped their dependency on Akt and FoxO1 signaling. Further, we identified several feeding-regulated lncRNAs, including the lncRNA Gm11967, whose expression was dependent upon the liver Akt-FoxO1 axis. Restoring Gm11967 expression in mice lacking liver Akt improved insulin sensitivity and induced glucokinase protein expression, indicating that Akt-dependent control of Gm11967 contributes to the translational control of glucokinase. More broadly, we have generated a unique genome-wide dataset that defines the feeding and Akt/FoxO1-dependent transcriptional changes in response to nutrient availability.
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Affiliation(s)
- Dominic Santoleri
- Biochemistry and Molecular Biophysics Graduate Group, University of Pennsylvania Biomedical Graduate Studies, Philadelphia, PA 19104, USA
- Institute of Diabetes, Obesity and Metabolism, Smilow Center for Translational Research, University of Pennsylvania Perelman School of Medicine, 3400 Civic Center Blvd, Building 421, Philadelphia, PA 19104, USA
| | - Hee-Woong Lim
- Division of Biomedical Informatics, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA
- Department of Pediatrics, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Matthew J. Emmett
- Department of Medicine, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Julian Stoute
- Biochemistry and Molecular Biophysics Graduate Group, University of Pennsylvania Biomedical Graduate Studies, Philadelphia, PA 19104, USA
- Department of Biochemistry and Biophysics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Matthew J. Gavin
- Institute of Diabetes, Obesity and Metabolism, Smilow Center for Translational Research, University of Pennsylvania Perelman School of Medicine, 3400 Civic Center Blvd, Building 421, Philadelphia, PA 19104, USA
| | - Jaimarie Sostre-Colón
- Institute of Diabetes, Obesity and Metabolism, Smilow Center for Translational Research, University of Pennsylvania Perelman School of Medicine, 3400 Civic Center Blvd, Building 421, Philadelphia, PA 19104, USA
| | - Kahealani Uehara
- Biochemistry and Molecular Biophysics Graduate Group, University of Pennsylvania Biomedical Graduate Studies, Philadelphia, PA 19104, USA
- Institute of Diabetes, Obesity and Metabolism, Smilow Center for Translational Research, University of Pennsylvania Perelman School of Medicine, 3400 Civic Center Blvd, Building 421, Philadelphia, PA 19104, USA
| | - Jaclyn E. Welles
- Institute of Diabetes, Obesity and Metabolism, Smilow Center for Translational Research, University of Pennsylvania Perelman School of Medicine, 3400 Civic Center Blvd, Building 421, Philadelphia, PA 19104, USA
| | - Kathy Fange Liu
- Biochemistry and Molecular Biophysics Graduate Group, University of Pennsylvania Biomedical Graduate Studies, Philadelphia, PA 19104, USA
- Department of Biochemistry and Biophysics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Mitchell A. Lazar
- Institute of Diabetes, Obesity and Metabolism, Smilow Center for Translational Research, University of Pennsylvania Perelman School of Medicine, 3400 Civic Center Blvd, Building 421, Philadelphia, PA 19104, USA
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Paul M. Titchenell
- Biochemistry and Molecular Biophysics Graduate Group, University of Pennsylvania Biomedical Graduate Studies, Philadelphia, PA 19104, USA
- Institute of Diabetes, Obesity and Metabolism, Smilow Center for Translational Research, University of Pennsylvania Perelman School of Medicine, 3400 Civic Center Blvd, Building 421, Philadelphia, PA 19104, USA
- Department of Physiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
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Sternisha SM, Whittington AC, Martinez Fiesco JA, Porter C, McCray MM, Logan T, Olivieri C, Veglia G, Steinbach PJ, Miller BG. Nanosecond-Timescale Dynamics and Conformational Heterogeneity in Human GCK Regulation and Disease. Biophys J 2020; 118:1109-1118. [PMID: 32023434 DOI: 10.1016/j.bpj.2019.12.036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 12/11/2019] [Accepted: 12/19/2019] [Indexed: 11/25/2022] Open
Abstract
Human glucokinase (GCK) is the prototypic example of an emerging class of proteins with allosteric-like behavior that originates from intrinsic polypeptide dynamics. High-resolution NMR investigations of GCK have elucidated millisecond-timescale dynamics underlying allostery. In contrast, faster motions have remained underexplored, hindering the development of a comprehensive model of cooperativity. Here, we map nanosecond-timescale dynamics and structural heterogeneity in GCK using a combination of unnatural amino acid incorporation, time-resolved fluorescence, and 19F nuclear magnetic resonance spectroscopy. We find that a probe inserted within the enzyme's intrinsically disordered loop samples multiple conformations in the unliganded state. Glucose binding and disease-associated mutations that suppress cooperativity alter the number and/or relative population of these states. Together, the nanosecond kinetics characterized here and the millisecond motions known to be essential for cooperativity provide a dynamical framework with which we address the origins of cooperativity and the mechanism of activated, hyperinsulinemia-associated, noncooperative variants.
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Affiliation(s)
- Shawn M Sternisha
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida
| | - A Carl Whittington
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida; Department of Biological Science, Florida State University, Tallahassee, Florida
| | | | - Carol Porter
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida
| | - Malcolm M McCray
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida
| | - Timothy Logan
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida; Institute of Molecular Biophysics, Florida State University, Tallahassee, Florida
| | - Cristina Olivieri
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, Minnesota
| | - Gianluigi Veglia
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, Minnesota; Department of Chemistry, University of Minnesota, Minneapolis, Minnesota
| | - Peter J Steinbach
- Center for Molecular Modeling, Center for Information Technology, National Institutes of Health, Bethesda, Maryland.
| | - Brian G Miller
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida.
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An intronic variant in the GCKR gene is associated with multiple lipids. Sci Rep 2019; 9:10240. [PMID: 31308433 PMCID: PMC6629684 DOI: 10.1038/s41598-019-46750-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Accepted: 07/02/2019] [Indexed: 12/25/2022] Open
Abstract
Previous studies have shown that an intronic variant rs780094 of the GCKR gene (glucokinase regulatory protein) is significantly associated with several metabolites, but the associations of this genetic variant with different lipids is largely unknown. Therefore, we applied metabolomics approach to measure metabolites in a large Finnish population sample (METSIM study) to investigate their associations with rs780094 of GCKR. We measured metabolites by mass spectrometry from 5,181 participants. P < 5.8 × 10−5 was considered as statistically significant given 857 metabolites included in statistical analyses. We found novel negative associations of the T allele of GCKR rs780094 with serine and threonine, and positive associations with two metabolites of tryptophan, indolelactate and N-acetyltryptophan. Additionally, we found novel significant positive associations of this genetic variant with 12 glycerolipids and 19 glycerophospholipids. Significant negative associations were found for three glycerophospholipids (all plasmalogen-cholines), and two sphingolipids. Significant novel associations were also found with gamma-glutamylthreonine, taurocholenate sulfate, and retinol. Our study adds new information about the pleiotropy of the GCKR gene, and shows the associations of the T allele of GCKR rs780094 with lipids.
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Matschinsky FM, Wilson DF. The Central Role of Glucokinase in Glucose Homeostasis: A Perspective 50 Years After Demonstrating the Presence of the Enzyme in Islets of Langerhans. Front Physiol 2019; 10:148. [PMID: 30949058 PMCID: PMC6435959 DOI: 10.3389/fphys.2019.00148] [Citation(s) in RCA: 152] [Impact Index Per Article: 30.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 02/07/2019] [Indexed: 01/05/2023] Open
Abstract
It is hypothesized that glucokinase (GCK) is the glucose sensor not only for regulation of insulin release by pancreatic β-cells, but also for the rest of the cells that contribute to glucose homeostasis in mammals. This includes other cells in endocrine pancreas (α- and δ-cells), adrenal gland, glucose sensitive neurons, entero-endocrine cells, and cells in the anterior pituitary. Glucose transport is by facilitated diffusion and is not rate limiting. Once inside, glucose is phosphorylated to glucose-6-phosphate by GCK in a reaction that is dependent on glucose throughout the physiological range of concentrations, is irreversible, and not product inhibited. High glycerol phosphate shuttle, pyruvate dehydrogenase, and pyruvate carboxylase activities, combined with low pentose-P shunt, lactate dehydrogenase, plasma membrane monocarboxylate transport, and glycogen synthase activities constrain glucose-6-phosphate to being metabolized through glycolysis. Under these conditions, glycolysis produces mostly pyruvate and little lactate. Pyruvate either enters the citric acid cycle through pyruvate dehydrogenase or is carboxylated by pyruvate carboxylase. Reducing equivalents from glycolysis enter oxidative phosphorylation through both the glycerol phosphate shuttle and citric acid cycle. Raising glucose concentration increases intramitochondrial [NADH]/[NAD+] and thereby the energy state ([ATP]/[ADP][Pi]), decreasing [Mg2+ADP] and [AMP]. [Mg2+ADP] acts through control of KATP channel conductance, whereas [AMP] acts through regulation of AMP-dependent protein kinase. Specific roles of different cell types are determined by the diverse molecular mechanisms used to couple energy state to cell specific responses. Having a common glucose sensor couples complementary regulatory mechanisms into a tightly regulated and stable glucose homeostatic network.
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Affiliation(s)
- Franz M Matschinsky
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - David F Wilson
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
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7
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Dietary Supplement of Large Yellow Tea Ameliorates Metabolic Syndrome and Attenuates Hepatic Steatosis in db/db Mice. Nutrients 2018; 10:nu10010075. [PMID: 29329215 PMCID: PMC5793303 DOI: 10.3390/nu10010075] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 12/28/2017] [Accepted: 01/09/2018] [Indexed: 02/06/2023] Open
Abstract
Yellow tea has been widely recognized for its health benefits. However, its effects and mechanism are largely unknown. The current study investigated the mechanism of dietary supplements of large yellow tea and its effects on metabolic syndrome and the hepatic steatosis in male db/db mice. Our data showed that dietary supplements of large yellow tea and water extract significantly reduced water intake and food consumption, lowered the serum total and low-density lipoprotein cholesterol and triglyceride levels, and significantly reduced blood glucose level and increased glucose tolerance in db/db mice when compared to untreated db/db mice. In addition, the dietary supplement of large yellow tea prevented the fatty liver formation and restored the normal hepatic structure of db/db mice. Furthermore, the dietary supplement of large yellow tea obviously reduced the lipid synthesis related to gene fatty acid synthase, the sterol regulatory element-binding transcription factor 1 and acetyl-CoA carboxylase α, as well as fatty acid synthase and sterol response element-binding protein 1 expression, while the lipid catabolic genes were not altered in the liver of db/db mice. This study substantiated that the dietary supplement of large yellow tea has potential as a food additive for ameliorating type 2 diabetes-associated symptoms.
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Zelent B, Bialas C, Gryczynski I, Chen P, Chib R, Lewerissa K, Corradini MG, Ludescher RD, Vanderkooi JM, Matschinsky FM. Tryptophan Fluorescence Yields and Lifetimes as a Probe of Conformational Changes in Human Glucokinase. J Fluoresc 2017; 27:1621-1631. [PMID: 28432632 PMCID: PMC6025808 DOI: 10.1007/s10895-017-2099-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2017] [Accepted: 04/04/2017] [Indexed: 10/19/2022]
Abstract
Five variants of glucokinase (ATP-D-hexose-6-phosphotransferase, EC 2.7.1.1) including wild type and single Trp mutants with the Trp residue at positions 65, 99, 167 and 257 were prepared. The fluorescence of Trp in all locations studied showed intensity changes when glucose bound, indicating that conformational change occurs globally over the entire protein. While the fluorescence quantum yield changes upon glucose binding, the enzyme's absorption spectra, emission spectra and fluorescence lifetimes change very little. These results are consistent with the existence of a dark complex for excited state Trp. Addition of glycerol, L-glucose, sucrose, or trehalose increases the binding affinity of glucose to the enzyme and increases fluorescence intensity. The effect of these osmolytes is thought to shift the protein conformation to a condensed, high affinity form. Based upon these results, we consider the nature of quenching of the Trp excited state. Amide groups are known to quench indole fluorescence and amides of the polypeptide chain make interact with excited state Trp in the relatively unstructured, glucose-free enzyme. Also, removal of water around the aromatic ring by addition of glucose substrate or osmolyte may reduce the quenching.
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Affiliation(s)
- Bogumil Zelent
- Department of Biochemistry and Biophysics and Diabetes Research Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
- Department of Food Science, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA.
| | - Chris Bialas
- Johnson Research Foundation, Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Ignacy Gryczynski
- Department of Cell Biology and Immunology, Center for Fluorescence Technologies and Nanomedicine, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Pan Chen
- Department of Biochemistry and Biophysics and Diabetes Research Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Rahul Chib
- Department of Food Science, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
| | - Karina Lewerissa
- Department of Food Science, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
| | - Maria G Corradini
- Department of Food Science, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
- Department of Food Science, University of Massachusetts Amherst, Massachusetts, MA, USA
| | - Richard D Ludescher
- Department of Food Science, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
| | - Jane M Vanderkooi
- Johnson Research Foundation, Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Franz M Matschinsky
- Department of Biochemistry and Biophysics and Diabetes Research Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
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Martínez R, Gutierrez-Nogués Á, Fernández-Ramos C, Velayos T, Vela A, Navas MÁ, Castaño L. Heterogeneity in phenotype of hyperinsulinism caused by activating glucokinase mutations: a novel mutation and its functional characterization. Clin Endocrinol (Oxf) 2017; 86:778-783. [PMID: 28247534 DOI: 10.1111/cen.13318] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 12/12/2016] [Accepted: 02/23/2017] [Indexed: 12/11/2022]
Abstract
BACKGROUND Mutations in the GCK gene lead to different forms of glucokinase (GCK)-disease, activating mutations cause hyperinsulinaemic hypoglycaemia while inactivating mutations cause monogenic diabetes. Hyperinsulinism (HI) is a heterogeneous condition with a significant genetic component. The major causes are channelopathies, the other forms are rare and being caused by mutations in genes such as GCK. OBJECTIVE To describe the clinical and genetic presentation of four families with activating GCK mutations, and to explore the pathogenicity of the novel mutation identified through functional studies. RESULTS Four cases of HI with mutations in GCK were identified. These include one novel mutation (p.Trp99Cys). Functional analysis of the purified mutant fusion protein glutathione-S-transferase (GST)-GCK-p.Trp99Cys demonstrated that p.Trp99Cys is an activating mutation as it induces a higher affinity for glucose and increases the relative activity index more than 11 times. Moreover, the thermal stability of the mutant protein was similar to that of its wild type. All patients were responsive to diazoxide treatment. One of the mutations arose de novo, and two were dominantly inherited, although only one of them from an HI affected parent. The age of presentation in our cases varied widely from the neonatal period to adulthood. CONCLUSION The clinical phenotype of the GCK activating mutation carriers was heterogeneous, the severity of symptoms and age at presentation varied markedly between affected individuals, even within the same family. The novel activating GCK mutation (p.Trp99Cys) has a strong activating effect in vitro although it has been identified in one case of a milder and late-onset form of HI.
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Affiliation(s)
- Rosa Martínez
- Endocrinology and Diabetes Research Group, BioCruces Health Research Institute, UPV-EHU, CIBERDEM, CIBERER, Cruces University Hospital, Barakaldo, Spain
| | - Ángel Gutierrez-Nogués
- Department of Biochemistry and Molecular Biology III, Faculty of Medicine, CIBERDEM and Hospital Clínico San Carlos Health Research Institute, Complutense University of Madrid, Madrid, Spain
| | - Concepción Fernández-Ramos
- Pediatric Endocrinology Section, BioCruces Health Research Institute, UPV/EHU, Basurto University Hospital, Bilbao, Spain
| | - Teresa Velayos
- Endocrinology and Diabetes Research Group, BioCruces Health Research Institute, UPV-EHU, CIBERDEM, CIBERER, Cruces University Hospital, Barakaldo, Spain
| | - Amaia Vela
- Pediatric Endocrinology Section, BioCruces Health Research Institute, UPV/EHU, Cruces University Hospital, CIBERDEM, CIBERER, Barakaldo, Bizkaia, Spain
| | - María-Ángeles Navas
- Department of Biochemistry and Molecular Biology III, Faculty of Medicine, CIBERDEM and Hospital Clínico San Carlos Health Research Institute, Complutense University of Madrid, Madrid, Spain
| | - Luis Castaño
- Endocrinology and Diabetes Research Group, BioCruces Health Research Institute, UPV-EHU, CIBERDEM, CIBERER, Cruces University Hospital, Barakaldo, Spain
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Cheung CYY, Tang CS, Xu A, Lee CH, Au KW, Xu L, Fong CHY, Kwok KHM, Chow WS, Woo YC, Yuen MMA, Cherny SS, Hai J, Cheung BMY, Tan KCB, Lam TH, Tse HF, Sham PC, Lam KSL. An Exome-Chip Association Analysis in Chinese Subjects Reveals a Functional Missense Variant of GCKR That Regulates FGF21 Levels. Diabetes 2017; 66:1723-1728. [PMID: 28385800 DOI: 10.2337/db16-1384] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Accepted: 03/10/2017] [Indexed: 11/13/2022]
Abstract
Fibroblast growth factor 21 (FGF21) is increasingly recognized as an important metabolic regulator of glucose homeostasis. Here, we conducted an exome-chip association analysis by genotyping 5,169 Chinese individuals from a community-based cohort and two clinic-based cohorts. A custom Asian exome-chip was used to detect genetic determinants influencing circulating FGF21 levels. Single-variant association analysis interrogating 70,444 single nucleotide polymorphisms identified a novel locus, GCKR, significantly associated with circulating FGF21 levels at genome-wide significance. In the combined analysis, the common missense variant of GCKR, rs1260326 (p.Pro446Leu), showed an association with FGF21 levels after adjustment for age and sex (P = 1.61 × 10-12; β [SE] = 0.14 [0.02]), which remained significant on further adjustment for BMI (P = 3.01 × 10-14; β [SE] = 0.15 [0.02]). GCKR Leu446 may influence FGF21 expression via its ability to increase glucokinase (GCK) activity. This can lead to enhanced FGF21 expression via elevated fatty acid synthesis, consequent to the inhibition of carnitine/palmitoyl-transferase by malonyl-CoA, and via increased glucose-6-phosphate-mediated activation of the carbohydrate response element binding protein, known to regulate FGF21 gene expression. Our findings shed new light on the genetic regulation of FGF21 levels. Further investigations to dissect the relationship between GCKR and FGF21, with respect to the risk of metabolic diseases, are warranted.
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Affiliation(s)
- Chloe Y Y Cheung
- Department of Medicine, The University of Hong Kong, Hong Kong, China
| | - Clara S Tang
- Department of Surgery, The University of Hong Kong, Hong Kong, China
| | - Aimin Xu
- Department of Medicine, The University of Hong Kong, Hong Kong, China
- The State Key Laboratory of Pharmaceutical Biotechnology, The University of Hong Kong, Hong Kong, China
- Research Centre of Heart, Brain, Hormone & Healthy Aging, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
- Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong, China
| | - Chi-Ho Lee
- Department of Medicine, The University of Hong Kong, Hong Kong, China
| | - Ka-Wing Au
- Department of Medicine, The University of Hong Kong, Hong Kong, China
| | - Lin Xu
- School of Public Health, The University of Hong Kong, Hong Kong, China
| | - Carol H Y Fong
- Department of Medicine, The University of Hong Kong, Hong Kong, China
| | - Kelvin H M Kwok
- Department of Medicine, The University of Hong Kong, Hong Kong, China
| | - Wing-Sun Chow
- Department of Medicine, The University of Hong Kong, Hong Kong, China
| | - Yu-Cho Woo
- Department of Medicine, The University of Hong Kong, Hong Kong, China
| | - Michele M A Yuen
- Department of Medicine, The University of Hong Kong, Hong Kong, China
| | - Stacey S Cherny
- Department of Psychiatry, The University of Hong Kong, Hong Kong, China
| | - JoJo Hai
- Department of Medicine, The University of Hong Kong, Hong Kong, China
| | | | - Kathryn C B Tan
- Department of Medicine, The University of Hong Kong, Hong Kong, China
| | - Tai-Hing Lam
- School of Public Health, The University of Hong Kong, Hong Kong, China
| | - Hung-Fat Tse
- Department of Medicine, The University of Hong Kong, Hong Kong, China
- Hong Kong-Guangdong Joint Laboratory on Stem Cell and Regenerative Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Pak-Chung Sham
- Department of Psychiatry, The University of Hong Kong, Hong Kong, China
- Centre for Genomic Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
- The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, China
| | - Karen S L Lam
- Department of Medicine, The University of Hong Kong, Hong Kong, China
- The State Key Laboratory of Pharmaceutical Biotechnology, The University of Hong Kong, Hong Kong, China
- Research Centre of Heart, Brain, Hormone & Healthy Aging, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
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11
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Hu Y, Tanaka T, Zhu J, Guan W, Wu JHY, Psaty BM, McKnight B, King IB, Sun Q, Richard M, Manichaikul A, Frazier-Wood AC, Kabagambe EK, Hopkins PN, Ordovas JM, Ferrucci L, Bandinelli S, Arnett DK, Chen YDI, Liang S, Siscovick DS, Tsai MY, Rich SS, Fornage M, Hu FB, Rimm EB, Jensen MK, Lemaitre RN, Mozaffarian D, Steffen LM, Morris AP, Li H, Lin X. Discovery and fine-mapping of loci associated with MUFAs through trans-ethnic meta-analysis in Chinese and European populations. J Lipid Res 2017; 58:974-981. [PMID: 28298293 PMCID: PMC5408616 DOI: 10.1194/jlr.p071860] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 02/17/2017] [Indexed: 11/20/2022] Open
Abstract
MUFAs are unsaturated FAs with one double bond and are derived from endogenous synthesis and dietary intake. Accumulating evidence has suggested that plasma and erythrocyte MUFA levels are associated with cardiometabolic disorders, including CVD, T2D, and metabolic syndrome (MS). Previous genome-wide association studies (GWASs) have identified seven loci for plasma and erythrocyte palmitoleic and oleic acid levels in populations of European origin. To identify additional MUFA-associated loci and the potential functional variant at each locus, we performed ethnic-specific GWAS meta-analyses and trans-ethnic meta-analyses in more than 15,000 participants of Chinese and European ancestry. We identified novel genome-wide significant associations for vaccenic acid at FADS1/2 and PKD2L1 [log10(Bayes factor) ≥ 8.07] and for gondoic acid at FADS1/2 and GCKR [log10(Bayes factor) ≥ 6.22], and also observed improved fine-mapping resolutions at FADS1/2 and GCKR loci. The greatest improvement was observed at GCKR, where the number of variants in the 99% credible set was reduced from 16 (covering 94.8 kb) to 5 (covering 19.6 kb, including a missense variant rs1260326) after trans-ethnic meta-analysis. We also confirmed the previously reported associations of PKD2L1, FADS1/2, GCKR, and HIF1AN with palmitoleic acid and of FADS1/2 and LPCAT3 with oleic acid in the Chinese-specific GWAS and the trans-ethnic meta-analyses. Pathway-based analyses suggested that the identified loci were in unsaturated FA metabolism and signaling pathways. Our findings provide novel insight into the genetic basis relevant to MUFA metabolism and biology.
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Affiliation(s)
- Yao Hu
- The Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of the Chinese Academy of Sciences, Shanghai, People's Republic of China
| | - Toshiko Tanaka
- Translational Gerontology Branch, National Institute on Aging, Baltimore, MD
| | - Jingwen Zhu
- The Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of the Chinese Academy of Sciences, Shanghai, People's Republic of China
| | - Weihua Guan
- Division of Biostatistics University of Minnesota, Minneapolis, MN
| | - Jason H Y Wu
- George Institute for Global Health, Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - Bruce M Psaty
- Cardiovascular Health Research Unit, Department of Medicine, University of Washington, Seattle, WA
- Group Health Research Institute, Group Health Cooperative, Seattle, WA
| | - Barbara McKnight
- Department of Biostatistics, University of Washington, Seattle, WA
| | - Irena B King
- Department of Internal Medicine, University of New Mexico, Albuquerque, NM
| | - Qi Sun
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA
- Department of Nutrition, Harvard T. H. Chan School of Public Health, Harvard University, Cambridge, MA
| | - Melissa Richard
- Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX
| | - Ani Manichaikul
- Center for Public Health Genomics, University of Virginia, Charlottesville, VA
- Biostatistics Section, Department of Public Health Sciences, University of Virginia, Charlottesville, VA
| | - Alexis C Frazier-Wood
- USDA Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX
| | - Edmond K Kabagambe
- Division of Epidemiology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Paul N Hopkins
- Department of Internal Medicine, University of Utah, Salt Lake City, UT
| | - Jose M Ordovas
- Nutrition and Genomics Laboratory, Jean Mayer-USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA
- Department of Epidemiology and Population Genetics, National Center for Cardiovascular Investigation, Madrid, Spain
| | - Luigi Ferrucci
- Translational Gerontology Branch, National Institute on Aging, Baltimore, MD
| | | | - Donna K Arnett
- Department of Epidemiology, University of Alabama at Birmingham, Birmingham, AL
| | - Yii-Der I Chen
- Institute for Translational Genomics and Population Sciences, Los Angeles BioMedical Research Institute at Harbor-UCLA Medical Center, Torrance, CA
| | - Shuang Liang
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN
| | - David S Siscovick
- Cardiovascular Health Research Unit, Department of Medicine, University of Washington, Seattle, WA
- Department of Epidemiology, School of Public Health, University of Washington, Seattle, WA
- New York Academy of Medicine, New York, NY
| | - Michael Y Tsai
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN
| | - Stephen S Rich
- Center for Public Health Genomics, University of Virginia, Charlottesville, VA
| | - Myriam Fornage
- Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX
| | - Frank B Hu
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA
- Department of Nutrition, Harvard T. H. Chan School of Public Health, Harvard University, Cambridge, MA
| | - Eric B Rimm
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA
- Department of Nutrition, Harvard T. H. Chan School of Public Health, Harvard University, Cambridge, MA
| | - Majken K Jensen
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA
- Department of Nutrition, Harvard T. H. Chan School of Public Health, Harvard University, Cambridge, MA
| | - Rozenn N Lemaitre
- Cardiovascular Health Research Unit, Department of Medicine, University of Washington, Seattle, WA
| | - Dariush Mozaffarian
- Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA
| | - Lyn M Steffen
- Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, MN
| | - Andrew P Morris
- Genetic and Genomic Epidemiology Unit, Wellcome Trust Centre for Human Genetics, Oxford, United Kingdom
| | - Huaixing Li
- The Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of the Chinese Academy of Sciences, Shanghai, People's Republic of China
| | - Xu Lin
- The Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of the Chinese Academy of Sciences, Shanghai, People's Republic of China
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12
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Zhang H, Shen WJ, Li Y, Bittner A, Bittner S, Tabassum J, Cortez YF, Kraemer FB, Azhar S. Microarray analysis of gene expression in liver, adipose tissue and skeletal muscle in response to chronic dietary administration of NDGA to high-fructose fed dyslipidemic rats. Nutr Metab (Lond) 2016; 13:63. [PMID: 27708683 PMCID: PMC5041401 DOI: 10.1186/s12986-016-0121-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2016] [Accepted: 09/14/2016] [Indexed: 02/06/2023] Open
Abstract
Nordihydroguaiaretic acid (NDGA), the main metabolite of Creosote Bush, has been shown to have profound effects on the core components of metabolic syndrome, including lowering of blood glucose, free fatty acids and triglyceride levels, attenuating elevated blood pressure in several rodent models of dyslipidemia, and improving body weight, insulin resistance, diabetes and hypertension. In the present study, a high-fructose diet fed rat model of hypertriglyceridemia, dyslipidemia, insulin resistance and hepatic steatosis was employed to investigate the global transcriptional changes in the lipid metabolizing pathways in three insulin sensitive tissues: liver, skeletal muscle and adipose tissue in response to chronic dietary administration of NDGA. Sprague-Dawley male rats (SD) were fed a chow (control) diet, high-fructose diet (HFrD) or HFrD supplemented with NDGA (2.5 g/kg diet) for eight weeks. Dietary administration of NDGA decreased plasma levels of TG, glucose, and insulin, and attenuated hepatic TG accumulation. DNA microarray expression profiling indicated that dietary administration of NDGA upregulated the expression of certain genes involved in fatty acid oxidation and their transcription regulator, PPARα, decreased the expression of a number of lipogenic genes and relevant transcription factors, and differentially impacted the genes of fatty acid transporters, acetyl CoA synthetases, elongases, fatty acid desaturases and lipid clearance proteins in liver, skeletal muscle and adipose tissues. These findings suggest that NDGA ameliorates hypertriglyceridemia and steatosis primarily by inhibiting lipogenesis and enhancing fatty acid catabolism in three major insulin responsive tissues by altering the expression of key enzyme genes and transcription factors involved in de novo lipogenesis and fatty acid oxidation.
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Affiliation(s)
- Haiyan Zhang
- Geriatric Research, Education and Clinical Center, VA Palo Alto Health Care System, Palo Alto, CA USA ; Division of Endocrinology, Stanford University, Stanford, CA USA ; Present Address: Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033 USA
| | - Wen-Jun Shen
- Geriatric Research, Education and Clinical Center, VA Palo Alto Health Care System, Palo Alto, CA USA ; Division of Endocrinology, Stanford University, Stanford, CA USA
| | - Yihang Li
- Geriatric Research, Education and Clinical Center, VA Palo Alto Health Care System, Palo Alto, CA USA ; Division of Endocrinology, Stanford University, Stanford, CA USA ; Present Address: Department of Pediatrics, Saint Louis University School of Medicine, St. Louis, MO USA
| | - Alex Bittner
- Geriatric Research, Education and Clinical Center, VA Palo Alto Health Care System, Palo Alto, CA USA
| | - Stefanie Bittner
- Geriatric Research, Education and Clinical Center, VA Palo Alto Health Care System, Palo Alto, CA USA
| | - Juveria Tabassum
- Geriatric Research, Education and Clinical Center, VA Palo Alto Health Care System, Palo Alto, CA USA
| | - Yuan F Cortez
- Geriatric Research, Education and Clinical Center, VA Palo Alto Health Care System, Palo Alto, CA USA
| | - Fredric B Kraemer
- Geriatric Research, Education and Clinical Center, VA Palo Alto Health Care System, Palo Alto, CA USA ; Division of Endocrinology, Stanford University, Stanford, CA USA
| | - Salman Azhar
- Geriatric Research, Education and Clinical Center, VA Palo Alto Health Care System, Palo Alto, CA USA ; Division of Endocrinology, Stanford University, Stanford, CA USA
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13
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Affiliation(s)
- Loranne Agius
- Institutes of Cellular Medicine and Ageing and Health, Medical School, Newcastle University, Newcastle upon Tyne, NE2 4HH United Kingdom;
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14
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Wessel J, Marrero D. Do Genes Determine Our Health? Implications for Designing Lifestyle Interventions and Drug Trials. CIRCULATION. CARDIOVASCULAR GENETICS 2016; 9:2-3. [PMID: 26884607 DOI: 10.1161/circgenetics.116.001367] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Affiliation(s)
- Jennifer Wessel
- From the Department of Epidemiology, Indiana University Fairbanks School of Public Health, Indianapolis (J.W.); and Department of Medicine, Indiana University School of Medicine, Indianapolis (J.W., D.M.).
| | - David Marrero
- From the Department of Epidemiology, Indiana University Fairbanks School of Public Health, Indianapolis (J.W.); and Department of Medicine, Indiana University School of Medicine, Indianapolis (J.W., D.M.)
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15
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Voevoda MI, Ivanova AA, Shakhtshneider EV, Ovsyannikova AK, Mikhailova SV, Astrakova KS, Voevoda SM, Rymar OD. Molecular genetics of maturity-onset diabetes of the young. TERAPEVT ARKH 2016. [DOI: 10.17116/terarkh2016884117-124] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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16
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Acetylation of glucokinase regulatory protein decreases glucose metabolism by suppressing glucokinase activity. Sci Rep 2015; 5:17395. [PMID: 26620281 PMCID: PMC4664969 DOI: 10.1038/srep17395] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Accepted: 10/14/2015] [Indexed: 01/01/2023] Open
Abstract
Glucokinase (GK), mainly expressed in the liver and pancreatic β-cells, is critical for maintaining glucose homeostasis. GK expression and kinase activity, respectively, are both modulated at the transcriptional and post-translational levels. Post-translationally, GK is regulated by binding the glucokinase regulatory protein (GKRP), resulting in GK retention in the nucleus and its inability to participate in cytosolic glycolysis. Although hepatic GKRP is known to be regulated by allosteric mechanisms, the precise details of modulation of GKRP activity, by post-translational modification, are not well known. Here, we demonstrate that GKRP is acetylated at Lys5 by the acetyltransferase p300. Acetylated GKRP is resistant to degradation by the ubiquitin-dependent proteasome pathway, suggesting that acetylation increases GKRP stability and binding to GK, further inhibiting GK nuclear export. Deacetylation of GKRP is effected by the NAD(+)-dependent, class III histone deacetylase SIRT2, which is inhibited by nicotinamide. Moreover, the livers of db/db obese, diabetic mice also show elevated GKRP acetylation, suggesting a broader, critical role in regulating blood glucose. Given that acetylated GKRP may affiliate with type-2 diabetes mellitus (T2DM), understanding the mechanism of GKRP acetylation in the liver could reveal novel targets within the GK-GKRP pathway, for treating T2DM and other metabolic pathologies.
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17
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Raimondo A, Rees MG, Gloyn AL. Glucokinase regulatory protein: complexity at the crossroads of triglyceride and glucose metabolism. Curr Opin Lipidol 2015; 26:88-95. [PMID: 25692341 PMCID: PMC4422901 DOI: 10.1097/mol.0000000000000155] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
PURPOSE OF REVIEW Glucokinase regulator (GCKR) encodes glucokinase regulatory protein (GKRP), a hepatocyte-specific inhibitor of the glucose-metabolizing enzyme glucokinase (GCK). Genome-wide association studies have identified a common coding variant within GCKR associated with multiple metabolic traits. This review focuses on recent insights into the critical role of GKRP in hepatic glucose metabolism that have stemmed from the study of human genetics. This knowledge has improved our understanding of glucose and lipid physiology and informed the development of targeted molecular therapeutics for diabetes. RECENT FINDINGS Rare GCKR variants have effects on GKRP expression, localization, and activity. These variants are collectively associated with hypertriglyceridaemia but are not causal. Crystal structures of GKRP and the GCK-GKRP complex have been solved, providing greater insight into the molecular interactions between these proteins. Finally, small molecules have been identified that directly bind GKRP and reduce blood glucose levels in rodent models of diabetes. SUMMARY GCKR variants across the allelic spectrum have effects on glucose and lipid homeostasis. Functional analysis has highlighted numerous molecular mechanisms for GKRP dysfunction. Hepatocyte-specific GCK activation via small molecule GKRP inhibition may be a new avenue for type 2 diabetes treatment, particularly considering evidence indicating GKRP loss-of-function alone does not cause hypertriglyceridaemia.
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Affiliation(s)
- Anne Raimondo
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Oxford, UK
| | - Matthew G. Rees
- Center for the Science of Therapeutics, Broad Institute, Cambridge, Massachusetts, USA
- Howard Hughes Medical Institute, Broad Institute, Cambridge, Massachusetts, USA
| | - Anna L. Gloyn
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Oxford, UK
- NIHR Oxford Biomedical Research Centre, ORH Trust, OCDEM, Churchill Hospital, Oxford, UK
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18
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Filipski KJ, Pfefferkorn JA. A patent review of glucokinase activators and disruptors of the glucokinase--glucokinase regulatory protein interaction: 2011-2014. Expert Opin Ther Pat 2014; 24:875-91. [PMID: 24821087 DOI: 10.1517/13543776.2014.918957] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Glucokinase (GK) is a key regulator of glucose homeostasis, and development of small molecule activators of this enzyme represents a promising new approach for the treatment of type 2 diabetes mellitus. AREAS COVERED This manuscript reviews small molecule patent disclosures between late 2011 and February 2014 for both GK activators (GKAs) and GK-glucokinase regulatory protein (GK-GKRP) disruptors. The review is organized by company and structural class. EXPERT OPINION The field of GKA research continues to progress, driven by research across many organizations. To date, > 20 candidates have entered clinical development with the most advanced in Phase II trials. Despite promising efficacy, a significant number of early candidates have been discontinued for various reasons including increased risk of hypoglycemia and lack of durability. Recent work in the field has focused on liver-selective activators, which have shown lower hypoglycemia risk, including the development of novel GK-GKRP disruptors that act to indirectly increase hepatic GK activity.
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Affiliation(s)
- Kevin J Filipski
- Cardiovascular, Metabolic & Endocrine Diseases Chemistry, Pfizer Worldwide Research & Development , 610 Main St, Cambridge, MA 02139 , USA +1 617 551 3267 ; +1 617 551 3082 ;
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