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Zhou K, Donnelly LA, Morris AD, Franks PW, Jennison C, Palmer CN, Pearson ER. Clinical and genetic determinants of progression of type 2 diabetes: a DIRECT study. Diabetes Care 2014; 37:718-724. [PMID: 24186880 PMCID: PMC4038744 DOI: 10.2337/dc13-1995] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To identify the clinical and genetic factors that explain why the rate of diabetes progression is highly variable between individuals following diagnosis of type 2 diabetes. RESEARCH DESIGN AND METHODS We studied 5,250 patients with type 2 diabetes using comprehensive electronic medical records in Tayside, Scotland, from 1992 onward. We investigated the association of clinical, biochemical, and genetic factors with the risk of progression of type 2 diabetes from diagnosis to the requirement of insulin treatment (defined as insulin treatment or HbA1c ≥8.5% [69 mmol/mol] treated with two or more noninsulin therapies). RESULTS Risk of progression was associated with both low and high BMI. In an analysis stratified by BMI and HbA1c at diagnosis, faster progression was independently associated with younger age at diagnosis, higher log triacylglyceride (TG) concentrations (hazard ratio [HR] 1.28 per mmol/L [95% CI 1.15-1.42]) and lower HDL concentrations (HR 0.70 per mmol/L [95% CI 0.55-0.87]). A high Genetic Risk Score derived from 61 diabetes risk variants was associated with a younger age at diagnosis and a younger age when starting insulin but was not associated with the progression rate from diabetes to the requirement of insulin treatment. CONCLUSIONS Increased TG and low HDL levels are independently associated with increased rate of progression of diabetes. The genetic factors that predispose to diabetes are different from those that cause rapid progression of diabetes, suggesting a difference in biological process that needs further investigation.
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Affiliation(s)
- Kaixin Zhou
- Division of Cardiovascular & Diabetes Medicine, Medical Research Institute, University of Dundee, DD1 9SY
| | - Louise A Donnelly
- Division of Cardiovascular & Diabetes Medicine, Medical Research Institute, University of Dundee, DD1 9SY
| | - Andrew D Morris
- Division of Cardiovascular & Diabetes Medicine, Medical Research Institute, University of Dundee, DD1 9SY
| | - Paul W Franks
- Department of Clinical Science, Genetic & Molecular Epidemiology Unit, Lund University, Malmö, Sweden; Department of Nutrition, Harvard School of Public Health, Boston, MA; Department of Public Health & Clinical Medicine, Umeå University, Umeå, Sweden
| | - Chris Jennison
- Department of Mathematical Sciences, University of Bath, Bath, BA2 7AY
| | - Colin Na Palmer
- Division of Cardiovascular & Diabetes Medicine, Medical Research Institute, University of Dundee, DD1 9SY
| | - Ewan R Pearson
- Division of Cardiovascular & Diabetes Medicine, Medical Research Institute, University of Dundee, DD1 9SY
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Liu Y, Wang M, Morris AD, Doney ASF, Leese GP, Pearson ER, Palmer CNA. Glycemic exposure and blood pressure influencing progression and remission of diabetic retinopathy: a longitudinal cohort study in GoDARTS. Diabetes Care 2013; 36:3979-84. [PMID: 24170761 PMCID: PMC3836116 DOI: 10.2337/dc12-2392] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE This study sought to investigate the progression and regression of diabetic retinopathy (DR) and the effects of population risk factors on the rates of transition across retinopathy stages. RESEARCH DESIGN AND METHODS The study cohort consisted of 44,871 observed DR events between the calendar years 1990 and 2011 for 4,758 diabetic patients who were diagnosed at 35 years of age or older. The first retinal observation was recorded within a year from diagnosis, and the result was recorded as free of retinopathy. A multistate Markov model was applied for analyzing the development of DR and its relation to the patterns of changes in risk factors. RESULTS We observed a consistent risk effect of HbA1c on the progression (no retinopathy to mild background DR [BDR] hazard ratio per SD of HbA1c [HR] 1.42 [95% CI 1.32-1.52], mild BDR to observable BDR HR 1.32 [95% CI 1.08-1.60], and observable BDR to severe nonproliferative/proliferative DR HR 2.23 [95% CI 1.16-4.29]). Similarly, systolic blood pressure (SBP) and diastolic blood pressure increased the risk for the transition from the asymptomatic phase to mild BDR (HR 1.20 [95% CI 1.11-1.30]) and the mild BDR to observable BDR (HR 1.87 [95% CI 1.46-2.40]), respectively. Regression from mild BDR to no DR was associated with lower SBP (HR 0.79 [95% CI 0.64-0.97]) and lower HbA1c (HR 0.76 [95% CI 0.64-0.89]). CONCLUSIONS Progression and regression of DR were strongly associated with blood pressure and glycemic exposure.
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Affiliation(s)
- Yiyuan Liu
- Corresponding author: Colin N.A. Palmer,
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153
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't Hart LM, Fritsche A, Nijpels G, van Leeuwen N, Donnelly LA, Dekker JM, Alssema M, Fadista J, Carlotti F, Gjesing AP, Palmer CNA, van Haeften TW, Herzberg-Schäfer SA, Simonis-Bik AMC, Houwing-Duistermaat JJ, Helmer Q, Deelen J, Guigas B, Hansen T, Machicao F, Willemsen G, Heine RJ, Kramer MHH, Holst JJ, de Koning EJP, Häring HU, Pedersen O, Groop L, de Geus EJC, Slagboom PE, Boomsma DI, Eekhoff EMW, Pearson ER, Diamant M. The CTRB1/2 locus affects diabetes susceptibility and treatment via the incretin pathway. Diabetes 2013; 62:3275-81. [PMID: 23674605 PMCID: PMC3749354 DOI: 10.2337/db13-0227] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The incretin hormone glucagon-like peptide 1 (GLP-1) promotes glucose homeostasis and enhances β-cell function. GLP-1 receptor agonists (GLP-1 RAs) and dipeptidyl peptidase-4 (DPP-4) inhibitors, which inhibit the physiological inactivation of endogenous GLP-1, are used for the treatment of type 2 diabetes. Using the Metabochip, we identified three novel genetic loci with large effects (30-40%) on GLP-1-stimulated insulin secretion during hyperglycemic clamps in nondiabetic Caucasian individuals (TMEM114; CHST3 and CTRB1/2; n = 232; all P ≤ 8.8 × 10(-7)). rs7202877 near CTRB1/2, a known diabetes risk locus, also associated with an absolute 0.51 ± 0.16% (5.6 ± 1.7 mmol/mol) lower A1C response to DPP-4 inhibitor treatment in G-allele carriers, but there was no effect on GLP-1 RA treatment in type 2 diabetic patients (n = 527). Furthermore, in pancreatic tissue, we show that rs7202877 acts as expression quantitative trait locus for CTRB1 and CTRB2, encoding chymotrypsinogen, and increases fecal chymotrypsin activity in healthy carriers. Chymotrypsin is one of the most abundant digestive enzymes in the gut where it cleaves food proteins into smaller peptide fragments. Our data identify chymotrypsin in the regulation of the incretin pathway, development of diabetes, and response to DPP-4 inhibitor treatment.
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Affiliation(s)
- Leen M 't Hart
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, the Netherlands.
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Abstract
Metformin is the first-line drug treatment for type 2 diabetes. Globally, over 100 million patients are prescribed this drug annually. Metformin was discovered before the era of target-based drug discovery and its molecular mechanism of action remains an area of vigorous diabetes research. An improvement in our understanding of metformin's molecular targets is likely to enable target-based identification of second-generation drugs with similar properties, a development that has been impossible up to now. The notion that 5' AMP-activated protein kinase (AMPK) mediates the anti-hyperglycaemic action of metformin has recently been challenged by genetic loss-of-function studies, thrusting the AMPK-independent effects of the drug into the spotlight for the first time in more than a decade. Key AMPK-independent effects of the drug include the mitochondrial actions that have been known for many years and which are still thought to be the primary site of action of metformin. Coupled with recent evidence of AMPK-independent effects on the counter-regulatory hormone glucagon, new paradigms of AMPK-independent drug action are beginning to take shape. In this review we summarise the recent research developments on the molecular action of metformin.
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Affiliation(s)
- Graham Rena
- Cardiovascular and Diabetes Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee, DD1 9SY UK
| | - Ewan R. Pearson
- Cardiovascular and Diabetes Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee, DD1 9SY UK
| | - Kei Sakamoto
- Nestlé Institute of Health Sciences SA, Campus EPFL, Quartier de l’innovation, bâtiment G, 1015 Lausanne, Switzerland
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155
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Macfarlane DP, O'Sullivan EP, Dorman S, Allison J, Ellingford A, Pearson ER, Mires GJ, Leese GP. The utility of retinal screening in gestational diabetes. Diabet Med 2013; 30:1009-10. [PMID: 23398520 DOI: 10.1111/dme.12152] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Revised: 01/03/2013] [Accepted: 02/05/2013] [Indexed: 11/28/2022]
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Abstract
Oral antidiabetic drugs (OADs) are used for more than a half-century in the treatment of type 2 diabetes. Only in the last five years, intensive research has been conducted in the pharmacogenetics of these drugs based mainly on the retrospective register studies, but only a handful of associations detected in these studies were replicated. The gene variants in CYP2C9, ABCC8/KCNJ11, and TCF7L2 were associated with the effect of sulfonylureas. CYP2C9 encodes sulfonylurea metabolizing cytochrome P450 isoenzyme 2C9, ABCC8 and KCNJ11 genes encode proteins constituting ATP-sensitive K(+) channel which is a therapeutic target for sulfonylureas, and TCF7L2 is a gene with the strongest association with type 2 diabetes. SLC22A1, SLC47A1, and ATM gene variants were repeatedly associated with the response to metformin. SLC22A1 and SLC47A1 encode metformin transporters OCT1 and MATE1, respectively. The function of a gene variant near ATM gene identified by a genome-wide association study is not elucidated so far. The first variant associated with the response to gliptins is a polymorphism in the proximity of CTRB1/2 gene which encodes chymotrypsinogen. Establishment of diabetes pharmacogenetics consortia and reduction in costs of genomics might lead to some significant clinical breakthroughs in this field in a near future.
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Affiliation(s)
- Matthijs L. Becker
- Department of Epidemiology, Erasmus MC, 3015 CE Rotterdam, The Netherlands
- Pharmacy Foundation of Haarlem Hospitals, 2035 RC Haarlem, The Netherlands
| | - Ewan R. Pearson
- Medical Research Institute, University of Dundee, Dundee DD1 9SY, UK
| | - Ivan Tkáč
- Department of Internal Medicine 4, Faculty of Medicine, P. J. Šafárik University, 041 80 Košice, Slovakia
- Department of Internal Medicine 4, L. Pasteur University Hospital, Rastislavova 43, 041 90 Košice, Slovakia
- *Ivan Tkáč:
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157
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Abstract
Early genome-wide association studies (GWAS) using relatively small samples have identified both rare and common genetic variants with large impact on severe adverse drug reactions, dosing, and efficacy. Here we outline the challenges and recent successes of the GWAS approach in disease genetics and the ways in which these can be applied to pharmacogenomics for biological discovery, determination of heritability, and personalized treatment. We highlight that the genetic architecture of drug efficacy reflects a complex trait yet that of adverse drug reactions more closely mirrors the architecture of Mendelian diseases and how this difference affects future study design. Given that multiple layers of biological data are increasingly available on large samples from biorepositories linked to electronic medical records, GWAS will remain a key component of the systems biology approach to uncovering small to moderate genetic determinants of drug response; these discoveries should move us closer to a personalized approach to health care.
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Affiliation(s)
- Kaixin Zhou
- Medical Research Institute, University of Dundee, Scotland, United Kingdom DD1 9SY.
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159
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Rena G, Pearson ER, Sakamoto K. Molecular action and pharmacogenetics of metformin: current understanding of an old drug. ACTA ACUST UNITED AC 2012. [DOI: 10.2217/dmt.12.42] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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160
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Abstract
AIMS To systematically review the evidence for the effect of vitamin D supplementation on glycaemia, insulin resistance, progression to diabetes and complications of diabetes. METHODS Systematic review and meta-analysis. We searched databases including MEDLINE, EMBASE and the Cochrane Library for randomized controlled trials comparing vitamin D or analogues with placebo. We extracted data on fasting glucose, glycaemic control, insulin resistance, insulin/C-peptide levels, micro- and macrovascular outcomes and progression from non-diabetes to diabetes. Studies were assessed independently by two reviewers according to a pre-specified protocol. RESULTS Fifteen trials were included in the systematic review. Trial reporting was of moderate, variable quality. Combining all studies, no significant improvement was seen in fasting glucose, HbA(1c) or insulin resistance in those treated with vitamin D compared with placebo. For patients with diabetes or impaired glucose tolerance, meta-analysis showed a small effect on fasting glucose (-0.32 mmol/l, 95%CI -0.57 to -0.07) and a small improvement in insulin resistance (standard mean difference -0.25, 95%CI -0.48 to -0.03). No effect was seen on glycated haemoglobin in patients with diabetes and no differences were seen for any outcome in patients with normal fasting glucose. Insufficient data were available to draw conclusions regarding micro- or macrovascular events; two trials failed to show a reduction in new cases of diabetes in patients treated with vitamin D. CONCLUSIONS There is currently insufficient evidence of beneficial effect to recommend vitamin D supplementation as a means of improving glycaemia or insulin resistance in patients with diabetes, normal fasting glucose or impaired glucose tolerance.
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Affiliation(s)
- P S George
- Ninewells Hospital and Medical School, University of Dundee, Dundee, UK
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161
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Palmer CNA, Maglio C, Pirazzi C, Burza MA, Adiels M, Burch L, Donnelly LA, Colhoun H, Doney AS, Dillon JF, Pearson ER, McCarthy M, Hattersley AT, Frayling T, Morris AD, Peltonen M, Svensson PA, Jacobson P, Borén J, Sjöström L, Carlsson LMS, Romeo S. Paradoxical lower serum triglyceride levels and higher type 2 diabetes mellitus susceptibility in obese individuals with the PNPLA3 148M variant. PLoS One 2012; 7:e39362. [PMID: 22724004 PMCID: PMC3377675 DOI: 10.1371/journal.pone.0039362] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Accepted: 05/18/2012] [Indexed: 01/23/2023] Open
Abstract
Background Obesity is highly associated with elevated serum triglycerides, hepatic steatosis and type 2 diabetes (T2D). The I148M (rs738409) genetic variant of patatin-like phospholipase domain-containing 3 gene (PNPLA3) is known to modulate hepatic triglyceride accumulation, leading to steatosis. No association between PNPLA3 I148M genotype and T2D in Europeans has been reported. Aim of this study is to examine the relationship between PNPLA3 I148M genotypes and serum triglycerides, insulin resistance and T2D susceptibility by testing a gene-environment interaction model with severe obesity. Methods and Findings PNPLA3 I148M was genotyped in a large obese cohort, the SOS study (n = 3,473) and in the Go-DARTS (n = 15,448), a T2D case-control study. Metabolic parameters were examined across the PNPLA3 I148M genotypes in participants of the SOS study at baseline and at 2- and 10-year follow up after bariatric surgery or conventional therapy. The associations with metabolic parameters were validated in the Go-DARTS study. Serum triglycerides were found to be lower in the PNPLA3 148M carriers from the SOS study at baseline and from the Go-DARTS T2D cohort. An increased risk for T2D conferred by the 148M allele was found in the SOS study (O.R. 1.09, 95% C.I. 1.01-1.39, P = 0.040) and in severely obese individuals in the Go-DARTS study (O.R. 1.37, 95% C.I. 1.13-1.66, P = 0.001). The 148M allele was no longer associated with insulin resistance or T2D after bariatric surgery in the SOS study and no association with the 148M allele was observed in the less obese (BMI<35) individuals in the Go-DARTS study (P for interaction = 0.002). This provides evidence for the obesity interaction with I48M allele and T2D risk in a large-scale cross-sectional and a prospective interventional study. Conclusions Severely obese individuals carrying the PNPLA3 148M allele have lower serum triglyceride levels, are more insulin resistant and more susceptible to T2D. This study supports the hypothesis that obesity-driven hepatic lipid accumulation may contribute to T2D susceptibility.
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Affiliation(s)
- Colin N. A. Palmer
- Medical Research Institute, Ninewells Hospital and Medical School, University of Dundee, Dundee, Scotland, United Kingdom
| | - Cristina Maglio
- Department of Molecular and Clinical Medicine and Center for Cardiovascular and Metabolic Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Carlo Pirazzi
- Department of Molecular and Clinical Medicine and Center for Cardiovascular and Metabolic Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Maria Antonella Burza
- Department of Molecular and Clinical Medicine and Center for Cardiovascular and Metabolic Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Martin Adiels
- Department of Molecular and Clinical Medicine and Center for Cardiovascular and Metabolic Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Lindsay Burch
- Medical Research Institute, Ninewells Hospital and Medical School, University of Dundee, Dundee, Scotland, United Kingdom
| | - Louise A. Donnelly
- Medical Research Institute, Ninewells Hospital and Medical School, University of Dundee, Dundee, Scotland, United Kingdom
| | - Helen Colhoun
- Medical Research Institute, Ninewells Hospital and Medical School, University of Dundee, Dundee, Scotland, United Kingdom
| | - Alexander S. Doney
- Medical Research Institute, Ninewells Hospital and Medical School, University of Dundee, Dundee, Scotland, United Kingdom
| | - John F. Dillon
- Medical Research Institute, Ninewells Hospital and Medical School, University of Dundee, Dundee, Scotland, United Kingdom
| | - Ewan R. Pearson
- Medical Research Institute, Ninewells Hospital and Medical School, University of Dundee, Dundee, Scotland, United Kingdom
| | - Mark McCarthy
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Oxford, United Kingdom
| | - Andrew T. Hattersley
- Peninsula NIHR Clinical Research Facility, Peninsula College of Medicine and Dentistry, University of Exeter, Exeter, United Kingdom
| | - Tim Frayling
- Peninsula NIHR Clinical Research Facility, Peninsula College of Medicine and Dentistry, University of Exeter, Exeter, United Kingdom
| | - Andrew D. Morris
- Medical Research Institute, Ninewells Hospital and Medical School, University of Dundee, Dundee, Scotland, United Kingdom
| | - Markku Peltonen
- Chronic Disease Epidemiology and Prevention Unit, Department of Chronic Disease Prevention, National Institute for Health and Welfare, Helsinki, Finland
| | - Per-Arne Svensson
- Department of Molecular and Clinical Medicine and Center for Cardiovascular and Metabolic Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Peter Jacobson
- Department of Molecular and Clinical Medicine and Center for Cardiovascular and Metabolic Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Jan Borén
- Department of Molecular and Clinical Medicine and Center for Cardiovascular and Metabolic Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Lars Sjöström
- Department of Molecular and Clinical Medicine and Center for Cardiovascular and Metabolic Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Lena M. S. Carlsson
- Department of Molecular and Clinical Medicine and Center for Cardiovascular and Metabolic Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Stefano Romeo
- Department of Molecular and Clinical Medicine and Center for Cardiovascular and Metabolic Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Department of Clinical and Experimental Medicine, University of Catanzaro, Catanzaro, Italy
- * E-mail:
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162
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McDonald TJ, McEneny J, Pearson ER, Thanabalasingham G, Szopa M, Shields BM, Ellard S, Owen KR, Malecki MT, Hattersley AT, Young IS. Lipoprotein composition in HNF1A-MODY: Differentiating between HNF1A-MODY and Type 2 diabetes. Clin Chim Acta 2012; 413:927-32. [DOI: 10.1016/j.cca.2012.02.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Revised: 02/06/2012] [Accepted: 02/07/2012] [Indexed: 10/14/2022]
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163
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Zhou K, Pearson ER. Research Highlights. Pharmacogenomics 2011. [DOI: 10.2217/pgs.11.30] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Affiliation(s)
- Kaixin Zhou
- Biomedical Research Institute, University of Dundee, DD1 9SY, UK
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164
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Petrie JR, Pearson ER, Sutherland C. Implications of genome wide association studies for the understanding of type 2 diabetes pathophysiology. Biochem Pharmacol 2010; 81:471-7. [PMID: 21111713 DOI: 10.1016/j.bcp.2010.11.010] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2010] [Revised: 11/12/2010] [Accepted: 11/12/2010] [Indexed: 12/20/2022]
Abstract
The rapid rise in prevalence of type 2 diabetes mellitus (T2DM) has been driven by changes in environmental factors - primarily increased caloric intake and reduced energy expenditure - resulting in reduced whole body insulin sensitivity (often termed insulin resistance). Insulin resistance has been proposed to be a major driver of progression to T2DM. However, of 38 individual susceptibility loci for T2DM recently identified by genome wide association studies, by far the majority code for proteins involved in β-cell function. In this review, we discuss the possible reasons for the paucity of insulin resistance genes and ask whether the new genetic susceptibility data should focus attention on β-cell targets in the development of therapies for T2DM.
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Affiliation(s)
- John R Petrie
- BHF Glasgow Cardiovascular Research Centre, University of Glasgow, 126 University Place, Glasgow G11 6TA, United Kingdom.
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165
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Rudman A, Pearson ER, Smith D, Srivastava R, Murphy MJ, Leese GP. Insulin resistance before and after parathyroidectomy in patients with primary hyperparathyroidism--a pilot study. Endocr Res 2010; 35:85-93. [PMID: 20408756 DOI: 10.3109/07435801003724503] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Primary hyperparathyroidism (PHPT) is associated with insulin resistance and an increased cardiovascular mortality. We aimed to see if parathyroidectomy improved insulin resistance. METHODS Twelve PHPT patients undergoing parathyroidectomy and ten control patients undergoing non-neck surgery were recruited to the study. Fasting venous blood samples were collected immediately pre-operatively and again at five to six weeks post-operatively. Samples were assayed for plasma glucose, serum insulin, total cholesterol, triglycerides, calcium, alkaline phosphatase, magnesium, parathyroid hormone (PTH), and haemoglobin A1c (HbA1c). Insulin resistance was calculated from fasting insulin and glucose values using Homeostasis Model Assessment (HOMA). RESULTS Parathyroidectomy decreased serum calcium (mean pre-op = 2.85 mmol/L, post-op 2.28 mmol/L, P < 0.001) and PTH concentrations (mean pre-op = 23.33 pmol/L, post-op = 10.23 pmol/L, P < 0.001) and increased phosphate concentration. However, there was no improvement in insulin resistance in the PHPT group at between 5 and 6 weeks post-operatively (geometric mean; pre-op = 0.88 (95% CI 0.59 - 1.33) vs. post-op = 0.88 (0.66 - 1.17) P = 0.95). In the control group, an increase in serum calcium was observed post-operatively (mean pre-op = 2.29 mmol/L, post-op = 2.35 mmol/L, P = 0.03). No change in insulin resistance was observed (geometric mean; pre-op = 1.37 (95% CI 0.89 - 2.11) vs. post-op = 1.38 (0.72 - 2.67) P = 0.96). CONCLUSION In summary, no significant change in insulin resistance post-parathyroidectomy in patients with PHPT was observed. This indicates that surgical treatment of PHPT does not improve insulin resistance for patients currently selected for parathyroidectomy.
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166
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Steele AM, Shields BM, Shepherd M, Ellard S, Hattersley AT, Pearson ER. Increased all-cause and cardiovascular mortality in monogenic diabetes as a result of mutations in the HNF1A gene. Diabet Med 2010; 27:157-61. [PMID: 20546258 DOI: 10.1111/j.1464-5491.2009.02913.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS To investigate all-cause and cardiovascular mortality in subjects with diabetes caused by a mutation in the hepatocyte nuclear factor 1alpha gene (HNF1A). METHODS We identified 39 British families with HNF1A mutations. Consenting individuals were asked details of age and cause of death of parents and siblings. Copies of death certificates were requested from the family or were obtained via the Offices for National Statistics. RESULTS Data were collated on 241 control subjects and 153 mutation carriers. Of those who died, 66% of mutation carriers died from a cardiovascular-related illness compared with 43% of control subjects (P = 0.02). Family members with HNF1A mutations died at a younger age than familial control subjects [all-cause hazard ratio, adjusting for sex and smoking status: 1.9 (95% confidence interval 1.2, 2.9, P = 0.006; cardiovascular hazard ratio: 2.3, confidence interval 1.3, 4.2, P = 0.006)]. CONCLUSIONS We have shown that individuals known to have diabetes caused by a mutation in the HNF1A gene have an increased risk of cardiovascular mortality compared with their unaffected family members. As with other forms of diabetes, consideration should be given to early statin therapy despite a seemingly protective lipid profile.
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Affiliation(s)
- A M Steele
- Peninsula NIHR Clinical Research Facility, Peninsula Medical School, Exeter
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Della Manna T, Battistim C, Radonsky V, Savoldelli RD, Damiani D, Kok F, Pearson ER, Ellard S, Hattersley AT, Reis AF. Glibenclamide unresponsiveness in a Brazilian child with permanent neonatal diabetes mellitus and DEND syndrome due to a C166Y mutation in KCNJ11 (Kir6.2) gene. ACTA ACUST UNITED AC 2009; 52:1350-5. [PMID: 19169493 DOI: 10.1590/s0004-27302008000800024] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2008] [Accepted: 11/04/2008] [Indexed: 12/13/2022]
Abstract
Heterozygous activating mutations of KCNJ11 (Kir6.2) are the most common cause of permanent neonatal diabetes mellitus (PNDM) and several cases have been successfully treated with oral sulfonylureas. We report on the attempted transfer of insulin therapy to glibenclamide in a 4-year old child with PNDM and DEND syndrome, bearing a C166Y mutation in KCNJ11. An inpatient transition from subcutaneous NPH insulin (0.2 units/kg/d) to oral glibenclamide (1 mg/kg/d and 1.5 mg/kg/d) was performed. Glucose and C-peptide responses stimulated by oral glucose tolerance test (OGTT), hemoglobin A1c levels, the 8-point self-measured blood glucose (SMBG) profile and the frequency of hypoglycemia episodes were analyzed, before and during treatment with glibenclamide. Neither diabetes control nor neurological improvements were observed. We concluded that C166Y mutation was associated with a form of PNDM insensitive to glibenclamide.
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Affiliation(s)
- Thais Della Manna
- Instituto da Criança, Hospital das Clínicas, Universidade de São Paulo, SP, Brasil.
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168
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Affiliation(s)
- E R Pearson
- Biomedical Research Institute, University of Dundee, Dundee, UK.
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169
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Zhou K, Donnelly LA, Kimber CH, Donnan PT, Doney AS, Leese G, Hattersley AT, McCarthy MI, Morris AD, Palmer CN, Pearson ER. Reduced-function SLC22A1 polymorphisms encoding organic cation transporter 1 and glycemic response to metformin: a GoDARTS study. Diabetes 2009; 58:1434-9. [PMID: 19336679 PMCID: PMC2682689 DOI: 10.2337/db08-0896] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
OBJECTIVE Metformin is actively transported into the liver by the organic cation transporter (OCT)1 (encoded by SLC22A1). In 12 normoglycemic individuals, reduced-function variants in SLC22A1 were shown to decrease the ability of metformin to reduce glucose excursion in response to oral glucose. We assessed the effect of two common loss-of-function polymorphisms in SLC22A1 on metformin response in a large cohort of patients with type 2 diabetes. RESEARCH DESIGN AND METHODS The Diabetes Audit and Research in Tayside Scotland (DARTS) database includes prescribing and biochemistry information and clinical phenotypes of all patients with diabetes within Tayside, Scotland, from 1992 onwards. R61C and 420del variants of SLC22A1 were genotyped in 3,450 patients with type 2 diabetes who were incident users of metformin. We assessed metformin response by modeling the maximum A1C reduction in 18 months after starting metformin and investigated whether a treatment target of A1C <7% was achieved. Sustained metformin effect on A1C between 6 and 42 months was also assessed, as was the time to metformin monotherapy failure. Covariates were SLC22A1 genotype, BMI, average drug dose, adherence, and creatinine clearance. RESULTS A total of 1,531 patients were identified with a definable metformin response. R61C and 420del variants did not affect the initial A1C reduction (P = 0.47 and P = 0.92, respectively), the chance of achieving a treatment target (P = 0.83 and P = 0.36), the average A1C on monotherapy up to 42 months (P = 0.44 and P = 0.75), or the hazard of monotherapy failure (P = 0.85 and P = 0.56). CONCLUSIONS The SLC22A1 loss-of-function variants, R61C and 420del, do not attenuate the A1C reduction achieved by metformin in patients with type 2 diabetes.
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Affiliation(s)
- Kaixin Zhou
- Dundee Diabetes Genetics Group, Biomedical Research Institute, University of Dundee, Dundee, U.K
| | - Louise A. Donnelly
- Dundee Diabetes Genetics Group, Biomedical Research Institute, University of Dundee, Dundee, U.K
| | - Charlotte H. Kimber
- Dundee Diabetes Genetics Group, Biomedical Research Institute, University of Dundee, Dundee, U.K
| | - Peter T. Donnan
- Health Informatics Centre, University of Dundee, Dundee, U.K
| | | | - Graham Leese
- Ninewells Hospital and Medical School, Dundee, U.K
- Diabetes Research Centre, University of Dundee, Dundee, U.K
| | - Andrew T. Hattersley
- Institute of Biomedical and Clinical Sciences, Peninsula Medical School, Exeter, U.K
| | - Mark I. McCarthy
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, U.K
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, U.K
| | - Andrew D. Morris
- Dundee Diabetes Genetics Group, Biomedical Research Institute, University of Dundee, Dundee, U.K
- Diabetes Research Centre, University of Dundee, Dundee, U.K
| | - Colin N.A. Palmer
- Dundee Diabetes Genetics Group, Biomedical Research Institute, University of Dundee, Dundee, U.K
- Diabetes Research Centre, University of Dundee, Dundee, U.K
| | - Ewan R. Pearson
- Dundee Diabetes Genetics Group, Biomedical Research Institute, University of Dundee, Dundee, U.K
- Diabetes Research Centre, University of Dundee, Dundee, U.K
- Corresponding author: Ewan R. Pearson,
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170
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Abstract
Genetic variation can impact on efficacy and risk of adverse events to commonly used oral agents in -diabetes. Metformin is not metabolized and its mechanism of action remains debated; however, several cation transporters have been identified. Variation in these pharmacokinetic genes might influence metformin response. Conversely, although the cytochrome P450 system has been implicated in sulfonylurea response in some small studies, to date variants affecting pharmacodynamics, including those in ABCC8 (SUR1) and TCF7L2, are the most promising. For thiazolidinedione response, variants in PPARG or ADIPOQ (adiponectin) have been variably associated with response. With increasing well-phenotyped cohorts and new methods, including genome-wide association studies, the next few years offer great hope to use pharmacogenetics to unravel drug and disease mechanisms, as well as the possibility to individualize therapy by genotype.
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Affiliation(s)
- Ewan R Pearson
- Biomedical Research Institute, Ninewells Hospital and Medical School, Ninewells Avenue, Dundee, DD1 9SY, UK.
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171
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Abstract
AIM Metformin is the most commonly prescribed oral agent used in the treatment of type 2 diabetes. It is effective at reducing glycosylated Haemoglobin (HbA1c) and decreasing microvascular and macrovascular disease. However, up to 25% of patients develop gastrointestinal side effects leading to cessation in 5-10% of users. Metformin XL (glucophage SR) is a once a day preparation that delays absorption, leading to decreased peak metformin concentrations. We hypothesised that the XL preparation of metformin would be better tolerated than the standard immediate release (IR) preparation leading to improved adherence to therapy. METHODS In a retrospective observational study, we studied adherence and glycaemic control in patients prescribed metformin IR and XL preparations in Tayside, UK. RESULTS Metformin XL was used by 137 patients during the study period. Overall adherence was greater in the XL group (80%) compared with the 10,772 patients in the IR group (72%, p = 0.0026). In the 40 patients who changed from metformin IR to metformin XL who had sufficient data to determine adherence, the adherence increased from 62% in the IR group to 81% in the XL group (p < 0.0001). This was associated with an HbA1c reduction from 9.1 to 8.4% (p = 0.0739, n = 29). CONCLUSIONS Metformin XL use is associated with increased adherence compared with the IR preparation, although the mechanism for this cannot be determined from this study. In patients intolerant of metformin IR the XL preparation should be considered.
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Affiliation(s)
- L A Donnelly
- Health Informatics Centre, University of Dundee, Dundee, UK
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172
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Wagner VM, Kremke B, Hiort O, Flanagan SE, Pearson ER. Transition from insulin to sulfonylurea in a child with diabetes due to a mutation in KCNJ11 encoding Kir6.2--initial and long-term response to sulfonylurea therapy. Eur J Pediatr 2009; 168:359-61. [PMID: 18548275 DOI: 10.1007/s00431-008-0757-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2008] [Revised: 04/28/2008] [Accepted: 04/29/2008] [Indexed: 12/25/2022]
Abstract
BACKGROUND Mutations in the KCNJ11 gene encoding the adenosine triphosphate (ATP)-sensitive potassium channel (K(ATP)) subunit Kir6.2 are the most frequent cause of diabetes in infancy. Sulfonylurea (SU) treatment restores insulin secretion in patients with KCNJ11 mutations. MATERIALS AND METHODS We report a 9-year-old boy who presented at the age of three months with diabetic ketoacidosis. Results Sequencing of the KCNJ11 gene revealed an R201H mutation. Therefore, he was transferred from insulin to oral SU therapy. He required a high-threshold dose before insulin could be discontinued. After transition, a subsequent dose reduction was necessary to avoid hypoglycemia. Improved sustained metabolic control without complications was achieved on a low SU maintenance dose twice daily over 36 months. CONCLUSION SU therapy is safe for patients with diabetes due to KCNJ11 mutations. The mechanism of a threshold dose and the twice-daily requirement needs further attention.
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Affiliation(s)
- Verena M Wagner
- Department of Pediatrics, Division of Pediatric Endocrinology and Diabetology, University of Lübeck, Lübeck, Germany.
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173
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de Wet H, Proks P, Lafond M, Aittoniemi J, Sansom MSP, Flanagan SE, Pearson ER, Hattersley AT, Ashcroft FM. A mutation (R826W) in nucleotide-binding domain 1 of ABCC8 reduces ATPase activity and causes transient neonatal diabetes. EMBO Rep 2008; 9:648-54. [PMID: 18497752 PMCID: PMC2475326 DOI: 10.1038/embor.2008.71] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2007] [Revised: 03/17/2008] [Accepted: 04/02/2008] [Indexed: 12/13/2022] Open
Abstract
Activating mutations in the pore-forming Kir6.2 (KCNJ11) and regulatory sulphonylurea receptor SUR1 (ABCC8) subunits of the K(ATP) channel are a common cause of transient neonatal diabetes mellitus (TNDM). We identified a new TNDM mutation (R826W) in the first nucleotide-binding domain (NBD1) of SUR1. The mutation was found in a region that heterodimerizes with NBD2 to form catalytic site 2. Functional analysis showed that this mutation decreases MgATP hydrolysis by purified maltose-binding protein MBP-NBD1 fusion proteins. Inhibition of ATP hydrolysis by MgADP or BeF was not changed. The results indicate that the ATPase cycle lingers in the post-hydrolytic MgADP.P(i)-bound state, which is associated with channel activation. The extent of MgADP-dependent activation of K(ATP) channel activity was unaffected by the R826W mutation, but the time course of deactivation was slowed. Channel inhibition by MgATP was reduced, leading to an increase in resting whole-cell currents. In pancreatic beta cells, this would lead to less insulin secretion and thereby diabetes.
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MESH Headings
- ATP-Binding Cassette Transporters/chemistry
- ATP-Binding Cassette Transporters/genetics
- Adenosine Diphosphate/pharmacology
- Adenosine Triphosphatases/chemistry
- Adenosine Triphosphatases/metabolism
- Adenosine Triphosphate/pharmacology
- Amino Acid Sequence
- Amino Acid Substitution
- Arginine/genetics
- Child
- Diabetes Mellitus/enzymology
- Diabetes Mellitus/genetics
- Humans
- Infant, Newborn
- Infant, Newborn, Diseases/enzymology
- Infant, Newborn, Diseases/genetics
- Ion Channel Gating/drug effects
- Kinetics
- Male
- Molecular Sequence Data
- Mutant Proteins/chemistry
- Mutation/genetics
- Potassium Channels, Inwardly Rectifying/chemistry
- Potassium Channels, Inwardly Rectifying/genetics
- Protein Structure, Secondary
- Protein Structure, Tertiary
- Receptors, Drug/chemistry
- Receptors, Drug/genetics
- Sulfonylurea Receptors
- Tryptophan/genetics
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Affiliation(s)
- Heidi de Wet
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK
| | - Peter Proks
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK
| | - Mathilde Lafond
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK
| | - Jussi Aittoniemi
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK
- Department of Biochemistry, University of Oxford, Oxford OX1 3PT, UK
| | - Mark S P Sansom
- Department of Biochemistry, University of Oxford, Oxford OX1 3PT, UK
| | - Sarah E Flanagan
- Institute of Biomedical and Clinical Science, Peninsula Medical School, Exeter EX2 5DW, UK
| | - Ewan R Pearson
- Division of Medicine and Therapeutics, Ninewells Hospital and Medical School, Dundee DD1 9SY, UK
| | - Andrew T Hattersley
- Institute of Biomedical and Clinical Science, Peninsula Medical School, Exeter EX2 5DW, UK
| | - Frances M Ashcroft
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK
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174
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Abstract
After many years of effort with only modest result, the last 5 years has seen a tremendous surge in our understanding of the genetics of diabetes. This review will focus on the therapeutic implications of diagnosing monogenic diabetes and the recent advances in type 1 and type 2 diabetes genetics following the development of Genome Wide Association studies.
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Affiliation(s)
- Ewan R Pearson
- Division of Medicine & Therapeutics, Ninewells Hospital & Medical School, Dundee DD19SY, United Kingdom.
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175
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Evans JMM, Ogston SA, Reimann F, Gribble FM, Morris AD, Pearson ER. No differences in mortality between users of pancreatic-specific and non-pancreatic-specific sulphonylureas: a cohort analysis. Diabetes Obes Metab 2008; 10:350-2. [PMID: 18093208 PMCID: PMC7237236 DOI: 10.1111/j.1463-1326.2007.00833.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
To assess whether users of pancreatic-specific sulphonylureas are at reduced risk of mortality and cardiovascular mortality compared with users of non-specific sulphonylureas, we conducted a cohort study in the population of Tayside, Scotland. We identified 3331 patients with type 2 diabetes who were newly treated with sulphonylureas between 1994 and 2001 and categorized them into those treated with only pancreatic-specific sulphonylureas and those treated with only non-specific sulphonylureas. The risks of mortality and cardiovascular mortality were compared in a survival analysis. There were 2914 patients treated with pancreatic-specific sulphonylureas only, of which 683 (23.4%) died. Of 186 patients treated with non-specific drugs only, 40 (21.5%) died. After adjusting for confounding factors, the adjusted risk ratios (with 95% CI) for mortality and cardiovascular mortality were 0.84 (0.61 to 1.17) and 0.81 (0.59 to 1.11) among the non-specific users compared with the pancreatic-specific users. This provides no evidence that there are differences between the two sulphonylureas types.
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176
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Pearson ER, Donnelly LA, Kimber C, Whitley A, Doney ASF, McCarthy MI, Hattersley AT, Morris AD, Palmer CNA. Variation in TCF7L2 influences therapeutic response to sulfonylureas: a GoDARTs study. Diabetes 2007; 56:2178-82. [PMID: 17519421 DOI: 10.2337/db07-0440] [Citation(s) in RCA: 243] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
OBJECTIVE There is considerable interindividual variation in sulfonylurea response in type 2 diabetes. Transcription factor 7-like 2 (TCF7L2) variants have been identified to be strongly associated with type 2 diabetes risk, probably due to decreased beta-cell function. We hypothesized that variation in TCF7L2 would influence response to sulfonylureas but not metformin. We studied the effect of TCF7L2 rs12255372 and rs7903146 genotypes on glycemic response. RESEARCH DESIGN AND METHODS The DARTS/MEMO (Diabetes Audit and Research Tayside/Medicines Monitoring Unit) collaboration database includes prescribing, biochemistry, and clinical phenotype of all patients with diabetes within Tayside, Scotland, from 1992. Of these, the TCF7L2 genotype was determined in 4,469 patients with type 2 diabetes recruited to GoDARTS (Genetics of Diabetes Audit and Research Tayside) between 1997 and July 2006. A total of 901 incident sulfonylurea users and 945 metformin users were identified. A logistic regression was used with treatment failure defined as an A1C >7% within 3-12 months after treatment initiation. Covariates included the TCF7L2 genotype, BMI, sex, age diagnosed, drug adherence, and drug dose. A1C pretreatment was available in a subset of patients (sulfonylurea n = 579; metformin n = 755). RESULTS Carriers of the risk allele were less likely to respond to sulfonylureas with an odds ratio (OR) for failure of 1.95 (95% CI 1.23-3.06; P = 0.005), comparing rs12255372 T/T vs. G/G. Including the baseline A1C strengthened this association (OR 2.16 [95% CI 1.21-3.86], P = 0.009). A similar, although slightly weaker, association was seen with rs7903146. No association was seen between metformin response and either single nucleotide polymorphism, after adjustment for baseline A1C. CONCLUSIONS TCF7L2 variants influence therapeutic response to sulfonylureas but not metformin. This study establishes that genetic variation can alter response to therapy in type 2 diabetes.
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Affiliation(s)
- Ewan R Pearson
- Division of Medicine and Therapeutics, University of Dundee, Dundee, UK.
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177
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Kimber CH, Doney ASF, Pearson ER, McCarthy MI, Hattersley AT, Leese GP, Morris AD, Palmer CNA. TCF7L2 in the Go-DARTS study: evidence for a gene dose effect on both diabetes susceptibility and control of glucose levels. Diabetologia 2007; 50:1186-91. [PMID: 17429603 DOI: 10.1007/s00125-007-0661-9] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2006] [Accepted: 02/19/2007] [Indexed: 12/14/2022]
Abstract
AIMS/HYPOTHESIS The gene encoding transcription factor 7-like 2 (TCF7L2) has been identified as a type 2 diabetes locus from genome-wide linkage studies and subsequent association analysis. We investigated the role of two common variants in TCF7L2 in a large case-control study recruited from the Tayside region of Scotland, UK. SUBJECTS AND METHODS We genotyped 6,516 participants for rs12255372 and rs7903146 and analysed the role in type 2 diabetes susceptibility using binary logistic regression. Age, sex and obesity status were examined as covariates. The distribution of the genotypes within different treatment groups of cases was examined. RESULTS Both variants were associated with type 2 diabetes (p < 10(-13)). The variants were present at very similar frequencies and were in strong linkage disequilibrium (R(2) = 0.88, D' = 0.89). A gene dosage effect of the rare allele of both variants was observed, the heterozygote CT group of rs7903146 having an odds ratio of 1.36 (95% CI 1.2-1.5, p=1.54 x 10(-7)) for type 2 diabetes and the TT homozygote having a greater risk (OR = 2.03, 95% CI 1.7-2.5, p=1.40 x 10(-12)). An interaction with sex was observed, the males displaying a higher degree of genotype-associated risk compared with the females (p = 0.023). The T allele was associated with increased HbA(1c) levels in both cases and controls, and with decreased BMI and waist circumference in case but not controls. The T allele was overrepresented in individuals requiring insulin treatment and underrepresented in the patients being managed by diet alone (p = 0.006). CONCLUSIONS We have confirmed TCF7L2 to be a diabetes locus in a large case-control study in Tayside, UK. Our data suggest that variants of TCF7L2 may be associated with increased disease severity and therapeutic failure.
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Affiliation(s)
- C H Kimber
- Population Pharmacogenetics Group, Biomedical Research Centre, Ninewells Hospital and Medical School, Dundee, UK
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178
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Pearson ER, Boj SF, Steele AM, Barrett T, Stals K, Shield JP, Ellard S, Ferrer J, Hattersley AT. Macrosomia and hyperinsulinaemic hypoglycaemia in patients with heterozygous mutations in the HNF4A gene. PLoS Med 2007; 4:e118. [PMID: 17407387 PMCID: PMC1845156 DOI: 10.1371/journal.pmed.0040118] [Citation(s) in RCA: 267] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2006] [Accepted: 02/01/2007] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Macrosomia is associated with considerable neonatal and maternal morbidity. Factors that predict macrosomia are poorly understood. The increased rate of macrosomia in the offspring of pregnant women with diabetes and in congenital hyperinsulinaemia is mediated by increased foetal insulin secretion. We assessed the in utero and neonatal role of two key regulators of pancreatic insulin secretion by studying birthweight and the incidence of neonatal hypoglycaemia in patients with heterozygous mutations in the maturity-onset diabetes of the young (MODY) genes HNF4A (encoding HNF-4alpha) and HNF1A/TCF1 (encoding HNF-1alpha), and the effect of pancreatic deletion of Hnf4a on foetal and neonatal insulin secretion in mice. METHODS AND FINDINGS We examined birthweight and hypoglycaemia in 108 patients from families with diabetes due to HNF4A mutations, and 134 patients from families with HNF1A mutations. Birthweight was increased by a median of 790 g in HNF4A-mutation carriers compared to non-mutation family members (p < 0.001); 56% (30/54) of HNF4A-mutation carriers were macrosomic compared with 13% (7/54) of non-mutation family members (p < 0.001). Transient hypoglycaemia was reported in 8/54 infants with heterozygous HNF4A mutations, but was reported in none of 54 non-mutation carriers (p = 0.003). There was documented hyperinsulinaemia in three cases. Birthweight and prevalence of neonatal hypoglycaemia were not increased in HNF1A-mutation carriers. Mice with pancreatic beta-cell deletion of Hnf4a had hyperinsulinaemia in utero and hyperinsulinaemic hypoglycaemia at birth. CONCLUSIONS HNF4A mutations are associated with a considerable increase in birthweight and macrosomia, and are a novel cause of neonatal hypoglycaemia. This study establishes a key role for HNF4A in determining foetal birthweight, and uncovers an unanticipated feature of the natural history of HNF4A-deficient diabetes, with hyperinsulinaemia at birth evolving to decreased insulin secretion and diabetes later in life.
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Affiliation(s)
- Ewan R Pearson
- Peninsula Medical School, Exeter, United Kingdom
- Division of Medicine and Therapeutics, Ninewells Hospital and Medical School, University of Dundee, Dundee, United Kingdom
| | - Sylvia F Boj
- Department of Endocrinology, Hospital Clinic de Barcelona, Barcelona, Spain
- Genomic Programming of Beta Cells Laboratory, Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
| | | | | | - Karen Stals
- Peninsula Medical School, Exeter, United Kingdom
| | - Julian P Shield
- Bristol Royal Hospital for Children, Bristol, United Kingdom
- University of Bristol, Bristol, United Kingdom
| | - Sian Ellard
- Peninsula Medical School, Exeter, United Kingdom
| | - Jorge Ferrer
- Department of Endocrinology, Hospital Clinic de Barcelona, Barcelona, Spain
- Genomic Programming of Beta Cells Laboratory, Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
| | - Andrew T Hattersley
- Peninsula Medical School, Exeter, United Kingdom
- * To whom correspondence should be addressed. E-mail:
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179
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Singh R, Pearson ER, Clark PM, Hattersley AT. The long-term impact on offspring of exposure to hyperglycaemia in utero due to maternal glucokinase gene mutations. Diabetologia 2007; 50:620-4. [PMID: 17216282 DOI: 10.1007/s00125-006-0541-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2006] [Accepted: 10/19/2006] [Indexed: 11/29/2022]
Abstract
AIMS/HYPOTHESIS There is strong evidence that maternal diabetes while offspring are in utero results in offspring beta cell dysfunction and diabetes or glucose intolerance. Offspring born to mothers with a mutation in the glucokinase gene (GCK) are a good model for studying exposure to moderate hyperglycaemia, as mutation carriers have fasting hyperglycaemia throughout life including during pregnancy. We assessed the long term effects of exposure to maternal hyperglycaemia in utero on beta cell function and glucose tolerance in adult offspring. MATERIALS AND METHODS We studied 86 adult offspring (mean age 40 years), 49 born to glucokinase mothers (exposed to hyperglycaemia in utero) and 37 born to glucokinase fathers (controls). We measured glucose tolerance during an OGTT and beta cell function using early insulin response (EIR); we also measured anthropometric data including birthweight. RESULTS Offspring of glucokinase mothers had a higher birthweight by 450 g (p<0.001), but no evidence of deterioration in glucose tolerance (2-h glucose 9.1 vs 8.6 mmol/l p=0.50) or reduced beta cell function (log EIR 1.40 vs 1.26, p=0.11) compared with offspring born to glucokinase fathers. CONCLUSIONS/INTERPRETATION The marked increase in birthweight shows that offspring born to affected mothers were exposed to increased glycaemia in utero. Despite this, there was no evidence of altered beta cell function or glucose tolerance. As previous human examples of marked programming by hyperglycaemia in utero have been in genetically predisposed offspring, we propose that our finding reflects the lack of genetic predisposition in the offspring to progressive beta cell dysfunction.
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Affiliation(s)
- R Singh
- Department of Molecular Medicine, Institute of Biomedical and Clinical Sciences, Peninsula Medical School, Exeter, and Division of Medicine and Therapeutics, Ninewells Hospital, Dundee, UK
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180
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Pearson ER, Flechtner I, Njølstad PR, Malecki MT, Flanagan SE, Larkin B, Ashcroft FM, Klimes I, Codner E, Iotova V, Slingerland AS, Shield J, Robert JJ, Holst JJ, Clark PM, Ellard S, Søvik O, Polak M, Hattersley AT. Switching from insulin to oral sulfonylureas in patients with diabetes due to Kir6.2 mutations. N Engl J Med 2006; 355:467-77. [PMID: 16885550 DOI: 10.1056/nejmoa061759] [Citation(s) in RCA: 646] [Impact Index Per Article: 35.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
BACKGROUND Heterozygous activating mutations in KCNJ11, encoding the Kir6.2 subunit of the ATP-sensitive potassium (K(ATP)) channel, cause 30 to 58 percent of cases of diabetes diagnosed in patients under six months of age. Patients present with ketoacidosis or severe hyperglycemia and are treated with insulin. Diabetes results from impaired insulin secretion caused by a failure of the beta-cell K(ATP) channel to close in response to increased intracellular ATP. Sulfonylureas close the K(ATP) channel by an ATP-independent route. METHODS We assessed glycemic control in 49 consecutive patients with Kir6.2 mutations who received appropriate doses of sulfonylureas and, in smaller subgroups, investigated the insulin secretory responses to intravenous and oral glucose, a mixed meal, and glucagon. The response of mutant K(ATP) channels to the sulfonylurea tolbutamide was assayed in xenopus oocytes. RESULTS A total of 44 patients (90 percent) successfully discontinued insulin after receiving sulfonylureas. The extent of the tolbutamide blockade of K(ATP) channels in vitro reflected the response seen in patients. Glycated hemoglobin levels improved in all patients who switched to sulfonylurea therapy (from 8.1 percent before treatment to 6.4 percent after 12 weeks of treatment, P<0.001). Improved glycemic control was sustained at one year. Sulfonylurea treatment increased insulin secretion, which was more highly stimulated by oral glucose or a mixed meal than by intravenous glucose. Exogenous glucagon increased insulin secretion only in the presence of sulfonylureas. CONCLUSIONS Sulfonylurea therapy is safe in the short term for patients with diabetes caused by KCNJ11 mutations and is probably more effective than insulin therapy. This pharmacogenetic response to sulfonylureas may result from the closing of mutant K(ATP) channels, thereby increasing insulin secretion in response to incretins and glucose metabolism. (ClinicalTrials.gov number, NCT00334711 [ClinicalTrials.gov].).
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Affiliation(s)
- Ewan R Pearson
- Institute of Biomedical and Clinical Sciences, Peninsula Medical School, Exeter, United Kingdom
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181
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Castleden HAJ, Shields B, Bingley PJ, Williams AJK, Sampson M, Walker M, Gibson JM, McCarthy MI, Hitman GA, Levy JC, Hattersley AT, Vaidya B, Pearson ER. GAD antibodies in probands and their relatives in a cohort clinically selected for Type 2 diabetes. Diabet Med 2006; 23:834-8. [PMID: 16911619 DOI: 10.1111/j.1464-5491.2006.01915.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIMS A subset of patients who present as if they have Type 2 diabetes have positive pancreatic autoantibodies, and have been referred to as having latent autoimmune diabetes in adults (LADA). We assessed the prevalence and clinical characteristics of patients with glutamic acid decarboxylase antibodies (GADA) in a cohort clinically selected for Type 2 diabetes and determined the presence of diabetes and GADA in their first-degree relatives. METHODS GADA were measured in 2059 subjects, not known to be related, and clinically selected as having Type 2 diabetes for genetic studies. Clinical characteristics were compared in GADA positive and GADA negative subjects. Diabetes and GAD antibody status were compared in 208 first-degree relatives of GADA positive and GADA negative probands. RESULTS Of the subjects, 136 (7%) were GADA positive. Compared with the GADA negative subjects, they were slimmer (P < 0.001), diagnosed at a younger age (P = 0.011) and progressed to insulin faster (P < 0.001). Thirty-three per cent of GADA positive subjects had a first-degree relative with diabetes compared with 42% of GADA negative subjects (P = 0.034). The overall prevalence of GADA was similar in the first-degree relatives of GADA positive and GADA negative probands (4 v 5%), and 19 of 22 (86%) diabetic relatives of GADA positive probands were GADA negative. CONCLUSION Despite clinically selecting a Type 2 diabetes cohort, 7% were GADA positive with an altered phenotype. These GADA positive patients had a strong family history of non-autoimmune diabetes. This suggests that, in this subgroup of patients, autoimmune pancreatic beta-cell destruction occurs on a background of Type 2 diabetes genetic susceptibility.
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Affiliation(s)
- H A J Castleden
- Institute of Biomedical and Clinical Sciences, Peninsula Medical School, Exeter, UK
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182
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Welters HJ, Senkel S, Klein-Hitpass L, Erdmann S, Thomas H, Harries LW, Pearson ER, Bingham C, Hattersley AT, Ryffel GU, Morgan NG. Conditional expression of hepatocyte nuclear factor-1beta, the maturity-onset diabetes of the young-5 gene product, influences the viability and functional competence of pancreatic beta-cells. J Endocrinol 2006; 190:171-81. [PMID: 16837621 DOI: 10.1677/joe.1.06768] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Mutations in the gene encoding hepatocyte nuclear factor (HNF)1beta result in maturity-onset diabetes of the young-(MODY)5, by impairing insulin secretory responses and, possibly, by reducing beta-cell mass. The functional role of HNF1beta in normal beta-cells is poorly understood; therefore, in the present study, wild-type (WT) HNF1beta, or one of two naturally occurring MODY5 mutations (an activating mutation, P328L329del, or a dominant-negative form, A263insGG) were conditionally expressed in the pancreatic beta-cell line, insulin-1 (INS-1), and the functional consequences examined. Surprisingly, overexpression of the dominant-negative mutant did not modify any of the functional properties of the cells studied (including insulin secretion, cell growth and viability). By contrast, expression of WT HNF1beta was associated with a time- and dose-dependent inhibition of INS-1 cell proliferation and a marked increase in apoptosis. Induction of WT HNF1beta also inhibited the insulin secretory response to nutrient stimuli, membrane depolarisation or activation of protein kinases A and C and this correlated with a significant decrease in pancrease-duodenum homeobox-1 protein levels. The attenuation of insulin secretion was, however, dissociated from the inhibition of proliferation and loss of viability, since expression of the P328L329del mutant led to a reduced rate of cell proliferation, but failed to induce apoptosis or to alter insulin secretion. Taken together, the present results suggest that mature rodent beta-cells are sensitive to increased expression of WT HNF1beta and they imply that the levels of this protein are tightly regulated to maintain secretory competence and cell viability.
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Affiliation(s)
- Hannah J Welters
- Institute of Biomedical and Clinical Science, Peninsula Medical School, Universities of Exeter and Plymouth, Research Way, Plymouth, Devon PL6 8BU, UK
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183
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Abstract
Defining the molecular genetics of diabetes gives new insight into the underlying etiology and so should help improve treatment. The genetic etiology is now known for most patients with beta-cell monogenic diabetes, allowing genetic classification. We review how this genetic knowledge alters treatment. Patients with a glucose-sensing beta-cell defect due to glucokinase mutations have regulated, mild, fasting hyperglycemia. Oral hypoglycemic agents or low-dose insulin rarely improve glycemic control. Patients with hepatic nuclear factor-1alpha (HNF1alpha) mutations have progressive beta-cell deterioration and require treatment. HNF1alpha patients are 4 times more sensitive to sulfonylureas than matched type 2 diabetic patients. This is partly due to greater insulin secretion, reflecting the fact that the defect in HNF1alpha deficiency precedes the K(ATP) channel where sulfonylureas act. HNF1beta is expressed in pancreatic stem cells before differentiation into endocrine or exocrine cells, so patients with HNF1beta mutations have reduced pancreatic development, resulting in early-onset diabetes and exocrine dysfunction. These patients usually rapidly require insulin and are not sensitive to sulfonylureas. Thirty-five to 50% of patients diagnosed with diabetes before 6 months have a mutation in Kir6.2. The mutated KATP channel in these patients does not close in response to increased ATP concentrations, but can be closed when sulfonylureas bind to the sulfonylurea receptor 1 subunit of the channel by an ATP-independent route. These patients are usually insulin dependent, but have excellent glycemic control on high-dose sulfonylureas tablets. In conclusion, the defining of molecular genetic etiology in monogenic diabetes has identified several specific beta-cell defects, and these are critical in determining the response to treatment.
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184
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Abstract
AIMS In treating Type 2 diabetes (T2DM), UK guidelines recommend metformin in obese and overweight patients, and either sulphonylureas or metformin in normal weight patients. Although other factors influence prescribing choice, a key objective in treating T2DM is to lower plasma glucose. There is little data on how glycaemic response to oral agents varies with body mass index (BMI). Therefore, we assessed current prescribing practice and effect of BMI on glycaemic response to sulphonylureas and metformin in a large population T2DM cohort. METHODS BMI was determined in 3856 T2DM patients on sulphonylurea or metformin monotherapy in 2001-2002. Patients were identified from the Diabetes Audit and Research in Tayside, Scotland (DARTS) database. In a linear regression, the effect of BMI and other confounders on drug response was assessed in 2064 treatment-naïve patients commencing sulphonylureas or metformin between 1994 and 2002. RESULTS In 2001-2002, metformin was more likely to be used in obese than non-obese patients: 13% normal weight, 33.6% overweight and 62.1% obese patients were treated with metformin. Glycaemic response to sulphonylureas was not influenced by BMI (P = 0.81). Metformin was more effective in lowering glucose in those with a lower BMI (r = -0.02, P = 0.02), although the clinical impact of this was small. The HbA(1c) reduction in non-obese patients was similar to that in obese patients (1.46% vs. 1.34%, P = 0.11). CONCLUSIONS Glycaemic response to metformin in non-obese and obese patients is similar, suggesting that an individual's BMI should not influence the choice of oral agent. Given the non-glycaemia-related benefits of metformin, it should be used in more non-obese patients than is current practice in Tayside, Scotland.
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Affiliation(s)
- L A Donnelly
- Department of Clinical Pharmacology, Ninewells Hospital and Medical School, University of Dundee, Dundee, UK
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185
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Brackenridge A, Pearson ER, Shojaee-Moradie F, Hattersley AT, Russell-Jones D, Umpleby AM. Contrasting insulin sensitivity of endogenous glucose production rate in subjects with hepatocyte nuclear factor-1beta and -1alpha mutations. Diabetes 2006; 55:405-11. [PMID: 16443774 DOI: 10.2337/diabetes.55.02.06.db05-1019] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Heterozygous mutations in the transcription factors hepatocyte nuclear factor (HNF)-1alpha and -1beta result in MODY (maturity-onset diabetes of the young). Despite structural similarity between HNF-1alpha and -1beta, HNF-1beta mutation carriers have hyperinsulinemia, whereas HNF-1alpha mutation carriers have normal or reduced insulin concentrations. We examined whether HNF-1beta mutation carriers are insulin resistant. The endogenous glucose production rate and rate of glucose uptake were measured with a two-step, low-dose (0.3 mU . kg(-1) . min(-1)) and high-dose (1.5 mU . kg(-1) . min(-1)) hyperinsulinemic-euglycemic clamp, with an infusion of [6,6-(2)H(2)]glucose, in six subjects with HNF-1alpha mutations, six subjects with HNF-1beta mutations, and six control subjects, matched for age, sex, and BMI. Endogenous glucose production rate was not suppressed by low-dose insulin in HNF-1beta subjects but was suppressed by 89% in HNF-1alpha subjects (P = 0.004) and 80% in control subjects (P < 0.001). Insulin-stimulated glucose uptake and suppression of lipolysis were similar in all groups at low- and high-dose insulin. Subjects with HNF-1beta mutations have reduced insulin sensitivity of endogenous glucose production but normal peripheral insulin sensitivity. This is likely to reflect reduced action of HNF-1beta in the liver and possibly the kidney. This may be mediated through regulation by HNF-1beta of the key gluconeogenic enzymes glucose-6-phosphatase or PEPCK.
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Affiliation(s)
- Anna Brackenridge
- Department of Diabetes and Endocrinology, Royal Surrey County Hospital, Guildford, UK
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186
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Pearson ER, Pruhova S, Tack CJ, Johansen A, Castleden HAJ, Lumb PJ, Wierzbicki AS, Clark PM, Lebl J, Pedersen O, Ellard S, Hansen T, Hattersley AT. Molecular genetics and phenotypic characteristics of MODY caused by hepatocyte nuclear factor 4alpha mutations in a large European collection. Diabetologia 2005; 48:878-85. [PMID: 15830177 DOI: 10.1007/s00125-005-1738-y] [Citation(s) in RCA: 143] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2004] [Accepted: 12/16/2004] [Indexed: 11/30/2022]
Abstract
AIMS/HYPOTHESIS Heterozygous mutations in the gene of the transcription factor hepatocyte nuclear factor 4alpha (HNF-4alpha) are considered a rare cause of MODY with only 14 mutations reported to date. The description of the phenotype is limited to single families. We investigated the genetics and phenotype of HNF-4alpha mutations in a large European Caucasian collection. METHODS HNF-4alpha was sequenced in 48 MODY probands, selected for a phenotype of HNF-1alpha MODY but negative for HNF-1alpha mutations. Clinical characteristics and biochemistry were compared between 54 HNF-4alpha mutation carriers and 32 familial controls from ten newly detected or previously described families. RESULTS Mutations in HNF-4alpha were found in 14/48 (29%) probands negative for HNF-1alpha mutations. The mutations found included seven novel mutations: S34X, D206Y, E276D, L332P, I314F, L332insCTG and IVS5nt+1G>A. I314F is the first reported de novo HNF-4alpha mutation. The average age of diagnosis was 22.9 years with frequent clinical evidence of sensitivity to sulphonylureas. Beta cell function, but not insulin sensitivity, was reduced in diabetic mutation carriers compared to control subjects (homeostasis model assessment of beta cell function 29% p<0.001 vs controls). HNF-4alpha mutations were associated with lower apolipoprotein A2 (p=0.001), A1 (p=0.04) and total HDL-cholesterol (p=0.02) than in control subjects. However, in contrast to some previous reports, levels of triglycerides and apolipoprotein C3 were normal. CONCLUSIONS/INTERPRETATION HNF-4alpha mutations are common when no HNF-1alpha mutation is found in strictly defined MODY families. The HNF-4alpha clinical phenotype and beta cell dysfunction are similar to HNF-1alpha MODY and are associated with reduced apolipoprotein A2 levels. We suggest that sequencing of HNF-4alpha should be performed in patients with clinical characteristics of HNF-1alpha MODY in whom mutations in HNF-1alpha are not found.
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Affiliation(s)
- E R Pearson
- Diabetes and Vascular Medicine, Institute of Biomedical and Clinical Science, Peninsula Medical School, Barrack Road, Exeter EX2 5AX, UK.
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187
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Sagen JV, Pearson ER, Johansen A, Spyer G, Søvik O, Pedersen O, Njølstad PR, Hattersley AT, Hansen T. Preserved insulin response to tolbutamide in hepatocyte nuclear factor-1alpha mutation carriers. Diabet Med 2005; 22:406-9. [PMID: 15787664 DOI: 10.1111/j.1464-5491.2005.01439.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS Diabetic subjects with mutations in the gene encoding hepatocyte nuclear factor (HNF)-1alpha (MODY3) are prone to develop hypoglycaemia at low doses of glibenclamide, interpreted as sulphonylurea hypersensitivity. The present study was undertaken to compare the plasma insulin responses to glucose and tolbutamide in HNF-1alpha mutation carriers with those of healthy control subjects. METHODS Seven mutation carriers; three normoglycaemic, two with impaired glucose tolerance, and two with newly detected diabetes, underwent an oral glucose tolerance test and a tolbutamide-modified intravenous glucose tolerance test with measurements of plasma insulin. Twenty-two healthy subjects served as controls. RESULTS The plasma insulin response to intravenous glucose was reduced in the HNF-1alpha mutation carriers compared to the control subjects, with an area under the curve (median (interquartile range)) of 812 min pmol/l (421, 1647) and 1933 min pmol/l (1521, 2908), respectively (P = 0.03). In striking contrast, the plasma insulin response to tolbutamide was preserved, with an area under the curve of 2109 min pmol/l (1126, 3172) and 2250 min pmol/l (1614, 3276) in the mutation carriers and control subjects, respectively. CONCLUSIONS HNF-1alpha mutation carriers are characterized by preserved tolbutamide-induced insulin secretion. Compared to healthy subjects, our MODY3 individuals did not show any increased serum insulin response to tolbutamide, suggesting that HNF-1alpha mutation carriers are not characterized by sulphonylurea hypersensitivity.
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Affiliation(s)
- J V Sagen
- Section of Paediatrics, Institute of Clinical Medicine, University of Bergen, Bergen, Norway.
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188
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Gloyn AL, Reimann F, Girard C, Edghill EL, Proks P, Pearson ER, Temple IK, Mackay DJG, Shield JPH, Freedenberg D, Noyes K, Ellard S, Ashcroft FM, Gribble FM, Hattersley AT. Relapsing diabetes can result from moderately activating mutations in KCNJ11. Hum Mol Genet 2005; 14:925-34. [PMID: 15718250 DOI: 10.1093/hmg/ddi086] [Citation(s) in RCA: 148] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Neonatal diabetes can either remit and hence be transient or else may be permanent. These two phenotypes were considered to be genetically distinct. Abnormalities of 6q24 are the commonest cause of transient neonatal diabetes (TNDM). Mutations in KCNJ11, which encodes Kir6.2, the pore-forming subunit of the ATP-sensitive potassium channel (K(ATP)), are the commonest cause of permanent neonatal diabetes (PNDM). In addition to diabetes, some KCNJ11 mutations also result in marked developmental delay and epilepsy. These mutations are more severe on functional characterization. We investigated whether mutations in KCNJ11 could also give rise to TNDM. We identified the three novel heterozygous mutations (G53S, G53R, I182V) in three of 11 probands with clinically defined TNDM, who did not have chromosome 6q24 abnormalities. The mutations co-segregated with diabetes within families and were not found in 100 controls. All probands had insulin-treated diabetes diagnosed in the first 4 months and went into remission by 7-14 months. Functional characterization of the TNDM associated mutations was performed by expressing the mutated Kir6.2 with SUR1 in Xenopus laevis oocytes. All three heterozygous mutations resulted in a reduction in the sensitivity to ATP when compared with wild-type (IC(50) approximately 30 versus approximately 7 microM, P-value for is all <0.01); however, this was less profoundly reduced than with the PNDM associated mutations. In conclusion, mutations in KCNJ11 are the first genetic cause for remitting as well as permanent diabetes. This suggests that a fixed ion channel abnormality can result in a fluctuating glycaemic phenotype. The multiple phenotypes associated with activating KCNJ11 mutations may reflect their severity in vitro.
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Affiliation(s)
- Anna L Gloyn
- Institute of Biomedical and Clinical Science, Peninsula Medical School, Barrack Road, Exeter EX2 5DW, USA
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189
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Abstract
AIMS Knockout mice lacking both copies of the hepatocyte nuclear factor 1 (HNF1) gene have altered serum levels of amino acids and generalized aminoaciduria. The aim of our study was to test whether alterations in serum amino acid levels were found in patients with mutations in the hepatocyte nuclear factor-1 alpha (HNF-1alpha) gene compared with controls. METHODS Fasting serum from 20 patients with HNF-1alpha mutations and 20 age, sex and body mass index-matched controls was analysed for 16 amino acids. Means were compared between the two groups and Z scores calculated. RESULTS There was no significant difference between patients with HNF-1alpha mutations and controls in serum levels of phenylalanine, arginine, citrulline or lysine as suggested by knockout mice models. Although serum levels of eight amino acids were different in the two groups, these were not significant after Bonferroni correction. CONCLUSIONS The alterations in serum amino acid levels seen in mice models are not seen in patients with mutations in the HNF-1alpha gene. This suggests differences in mouse and man in the regulation of amino acid transport and has not provided us with a phenotypic marker to use before confirmatory genetic testing.
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Affiliation(s)
- A Stride
- Department of Diabetes and Vascular Medicine, Peninsula Medical School, Exeter, UK
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190
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Pearson ER, Badman MK, Lockwood CR, Clark PM, Ellard S, Bingham C, Hattersley AT. Contrasting diabetes phenotypes associated with hepatocyte nuclear factor-1alpha and -1beta mutations. Diabetes Care 2004; 27:1102-7. [PMID: 15111528 DOI: 10.2337/diacare.27.5.1102] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Mutations in the highly homologous transcription factors hepatocyte nuclear factor (HNF)-1alpha and -1beta cause maturity-onset diabetes of the young types 3 and 5, respectively. Diabetes due to HNF-1alpha mutations is well characterized. However, physiological assessment of the HNF-1beta phenotype is limited. We aimed to test the hypothesis that the diabetes phenotype due to HNF-1beta mutations is similar to that in HNF-1alpha. RESEARCH DESIGN AND METHODS Fasting biochemistry and a tolbutamide-modified intravenous glucose tolerance test (IVGTT) were compared in matched HNF-1beta, HNF-1alpha, type 2 diabetic, and control subjects. Homeostasis model assessment indexes were determined from fasting insulin and glucose. The peak measures for the insulin increment after tolbutamide and for the insulin increment after glucose were determined from the IVGTT. RESULTS The HNF-1beta patients showed a 2.4-fold reduction in insulin sensitivity compared with the HNF-1alpha patients (P = 0.001) with fasting insulin concentrations 2.7-fold higher (P = 0.004). HNF-1beta patients had lower HDL cholesterol (1.17 vs. 1.46 mmol/l; P = 0.009) and higher triglyceride (2.2 vs. 1.35 mmol/l; P = 0.015) levels than HNF-1alpha patients. The HNF-1beta patients had similar beta-cell responses to tolbutamide and glucose as the type 2 diabetic patients, but in the HNF-1alpha patients, the tolbutamide response was considerably increased relative to the response to glucose (P = 0.002). CONCLUSIONS HNF-1beta patients have a different diabetes phenotype than HNF-1alpha patients. Those with HNF-1beta mutations have hyperinsulinemia and associated dyslipidemia consistent with insulin resistance and may have a different beta-cell defect. This suggests that despite considerable homology and a shared binding site, HNF-1alpha and HNF-1beta have a different role in maintaining normal glucose homeostasis. This result suggests a new etiological pathway for insulin resistance involving HNF-1beta.
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Affiliation(s)
- Ewan R Pearson
- Diabetes and Vascular Medicine, Peninsula Medical School, Exeter, UK
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191
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Gloyn AL, Pearson ER, Antcliff JF, Proks P, Bruining GJ, Slingerland AS, Howard N, Srinivasan S, Silva JMCL, Molnes J, Edghill EL, Frayling TM, Temple IK, Mackay D, Shield JPH, Sumnik Z, van Rhijn A, Wales JKH, Clark P, Gorman S, Aisenberg J, Ellard S, Njølstad PR, Ashcroft FM, Hattersley AT. Activating mutations in the gene encoding the ATP-sensitive potassium-channel subunit Kir6.2 and permanent neonatal diabetes. N Engl J Med 2004; 350:1838-49. [PMID: 15115830 DOI: 10.1056/nejmoa032922] [Citation(s) in RCA: 792] [Impact Index Per Article: 39.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Patients with permanent neonatal diabetes usually present within the first three months of life and require insulin treatment. In most, the cause is unknown. Because ATP-sensitive potassium (K(ATP)) channels mediate glucose-stimulated insulin secretion from the pancreatic beta cells, we hypothesized that activating mutations in the gene encoding the Kir6.2 subunit of this channel (KCNJ11) cause neonatal diabetes. METHODS We sequenced the KCNJ11 gene in 29 patients with permanent neonatal diabetes. The insulin secretory response to intravenous glucagon, glucose, and the sulfonylurea tolbutamide was assessed in patients who had mutations in the gene. RESULTS Six novel, heterozygous missense mutations were identified in 10 of the 29 patients. In two patients the diabetes was familial, and in eight it arose from a spontaneous mutation. Their neonatal diabetes was characterized by ketoacidosis or marked hyperglycemia and was treated with insulin. Patients did not secrete insulin in response to glucose or glucagon but did secrete insulin in response to tolbutamide. Four of the patients also had severe developmental delay and muscle weakness; three of them also had epilepsy and mild dysmorphic features. When the most common mutation in Kir6.2 was coexpressed with sulfonylurea receptor 1 in Xenopus laevis oocytes, the ability of ATP to block mutant K(ATP) channels was greatly reduced. CONCLUSIONS Heterozygous activating mutations in the gene encoding Kir6.2 cause permanent neonatal diabetes and may also be associated with developmental delay, muscle weakness, and epilepsy. Identification of the genetic cause of permanent neonatal diabetes may facilitate the treatment of this disease with sulfonylureas.
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Affiliation(s)
- Anna L Gloyn
- Institute of Biomedical and Clinical Science, Peninsula Medical School, Exeter, United Kingdom
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192
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Richter S, Shih DQ, Pearson ER, Wolfrum C, Fajans SS, Hattersley AT, Stoffel M. Regulation of apolipoprotein M gene expression by MODY3 gene hepatocyte nuclear factor-1alpha: haploinsufficiency is associated with reduced serum apolipoprotein M levels. Diabetes 2003; 52:2989-95. [PMID: 14633861 DOI: 10.2337/diabetes.52.12.2989] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Hepatocyte nuclear factor-1a (HNF-1alpha) is a transcription factor that plays an important role in regulation of gene expression in pancreatic beta-cells, intestine, kidney, and liver. Heterozygous mutations in the HNF-1alpha gene are responsible for maturity-onset diabetes of the young (MODY3), which is characterized by pancreatic beta-cell-deficient insulin secretion. HNF-1alpha is a major transcriptional regulator of many genes expressed in the liver. However, no liver defect has been identified in individuals with HNF-1alpha mutations. In this study, we show that Hnf-1alpha is a potent transcriptional activator of the gene encoding apolipoprotein M (apoM), a lipoprotein that is associated with the HDL particle. Mutant Hnf-1alpha(-/-) mice completely lack expression of apoM in the liver and the kidney. Serum apoM levels in Hnf-1alpha(+/-) mice are reduced approximately 50% compared with wild-type animals and are absent in the HDL and HDLc fractions of Hnf-1alpha(-/-). We analyzed the apoM promoter and identified a conserved HNF-1 binding site. We show that Hnf-1alpha is a potent activator of the apoM promoter, that a specific mutation in the HNF-1 binding site abolished transcriptional activation of the apoM gene, and that Hnf-1alpha protein can bind to the Hnf-1 binding site of the apoM promoter in vitro. To investigate whether patients with mutations in HNF-1alpha mutations (MODY3) have reduced serum apoM levels, we measured apoM levels in the serum of nine HNF-1alpha/MODY3 patients, nine normal matched control subjects (HNF-1alpha(+/+)), and nine HNF-4alpha/MODY1 subjects. Serum levels of apoM were decreased in HNF-1alpha/MODY3 subjects when compared with control subjects (P < 0.02) as well as with HNF-4alpha/MODY1 subjects, indicating that HNF-1alpha haploinsufficiency rather than hyperglycemia is the primary cause of decreased serum apoM protein concentrations. This study demonstrates that HNF-1alpha is required for apoM expression in vivo and that heterozygous HNF-1alpha mutations lead to an HNF-1alpha-dependent impairment of apoM expression. ApoM levels may be a useful serum marker for the identification of MODY3 patients.
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Affiliation(s)
- Symi Richter
- Laboratory of Metabolic Diseases, Rockefeller University, New York, New York 10021, USA
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193
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Shepherd M, Pearson ER, Houghton J, Salt G, Ellard S, Hattersley AT. No deterioration in glycemic control in HNF-1alpha maturity-onset diabetes of the young following transfer from long-term insulin to sulphonylureas. Diabetes Care 2003; 26:3191-2. [PMID: 14578267 DOI: 10.2337/diacare.26.11.3191-a] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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194
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Abstract
BACKGROUND Type 2 diabetes shows evidence of underlying heterogeneity. No studies have assessed whether different causes for diabetes change the response to oral hypoglycaemic therapy. In a few cases, patients with diabetes caused by mutations in the hepatocyte nuclear factor 1alpha (HNF-1alpha) gene have been described as sensitive to the hypoglycaemic effects of sulphonylureas. We aimed to see whether the glycaemic response to the sulphonylurea gliclazide and the biguanide metformin differed in HNF-1alpha diabetes and type 2 diabetes, and to investigate the mechanism for differences in sulphonylurea sensitivity. METHODS We did a randomised crossover trial of glicazide and metformin in 36 patients, either with diabetes caused by HNF-1alpha mutations or type 2 diabetes, who were matched for body-mass index and fasting plasma glucose. The primary outcome was reduction in fasting plasma glucose. Analysis was by intention to treat. We assessed possible mechanisms for sulphonylurea sensitivity through insulin sensitivity, insulin secretory response to glucose and tolbutamide, and tolbutamide clearance. FINDINGS Patients with HNF-1alpha diabetes had a 5.2-fold greater response to gliclazide than to metformin (fasting plasma glucose reduction 4.7 vs 0.9 mmol/L, p=0.0007) and 3.9-fold greater response to gliclazide than those with type 2 diabetes (p=0.002). Patients with HNF-1alpha diabetes had a strong insulin secretory response to intravenous tolbutamide despite a small response to intravenous glucose, and were more insulin sensitive than those with type 2 diabetes. Sulphonylurea metabolism was similar in both patient groups. INTERPRETATION The cause of hyperglycaemia changes the response to hypoglycaemic drugs; HNF-1alpha diabetes has marked sulphonylurea sensitivity. This pharmacogenetic effect is consistent with models of HNF-1alpha deficiency, which show that the beta-cell defect is upstream of the sulphonylurea receptor. Definition of the genetic basis of hyperglycaemia has implications for patient management.
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Affiliation(s)
- Ewan R Pearson
- Diabetes and Vascular Medicine, Peninsula Medical School, Exeter, UK
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Bingham C, Ellard S, van't Hoff WG, Simmonds HA, Marinaki AM, Badman MK, Winocour PH, Stride A, Lockwood CR, Nicholls AJ, Owen KR, Spyer G, Pearson ER, Hattersley AT. Atypical familial juvenile hyperuricemic nephropathy associated with a hepatocyte nuclear factor-1beta gene mutation. Kidney Int 2003; 63:1645-51. [PMID: 12675839 DOI: 10.1046/j.1523-1755.2003.00903.x] [Citation(s) in RCA: 123] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Familial juvenile hyperuricemic nephropathy (FJHN) is a dominantly inherited condition characterized by young-onset hyperuricemia, gout, and renal disease. The etiologic genes are unknown, although a locus on chromosome 16 has been identified in some kindreds. Mutations in the gene encoding hepatocyte nuclear factor (HNF)-1beta have been associated with dominant inheritance of a variety of disorders of renal development, particularly renal cystic disease and early onset diabetes; hyperuricemia has been reported in some kindreds. METHODS To assess a possible role for the HNF-1beta gene in some FJHN kindreds we sequenced the HNF-1beta gene in subjects from three unrelated FJHN families with atypical features of renal cysts or abnormalities of renal development. We also compared serum urate levels in subjects with HNF-1beta mutations with populations of controls, type 2 diabetic subjects, and subjects with mild chronic renal failure without HNF-1beta mutations. RESULTS A splice-site mutation in intron 2, designated IVS2+1G>T, showed complete co-segregation with FJHN in one family with diabetes. Serum urate levels were significantly higher in the HNF-1beta subjects compared with the normal control subjects (384 micromol/L vs. 264 micromol/L, P = 0.002) and the type 2 diabetic subjects (397 micromol/L vs. 271 micromol/L, P = 0.01). Comparison of serum urate levels in the HNF-1beta subjects with gender-matched subjects with renal impairment of other causes did not reach significance (402 micromol/L vs. 352 micromol/L, P = 0.2). CONCLUSION Hyperuricemia and young-onset gout are consistent features of the phenotype associated with HNF-1beta mutations, but the mechanism is uncertain. Families with HNF-1beta mutations may fit diagnostic criteria for FJHN. Identification of HNF-1beta patients by recognizing the features of diabetes and disorders of renal development is important in resolving the genetic heterogeneity in FJHN.
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Affiliation(s)
- Coralie Bingham
- Diabetes and Vascular Medicine, Peninsula Medical School, Exeter, United Kingdom.
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Waller SC, Rees L, Woolf AS, Ellard S, Pearson ER, Hattersley AT, Bingham C. Severe hyperglycemia after renal transplantation in a pediatric patient with a mutation of the hepatocyte nuclear factor-1beta gene. Am J Kidney Dis 2002; 40:1325-30. [PMID: 12460054 DOI: 10.1053/ajkd.2002.36915] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
After renal transplantation for congenital cystic kidney disease of unknown origin, a 14-year-old boy, who was previously normoglycemic, had "steroid-induced" diabetes mellitus, which was treated with insulin. Transplant failure from chronic rejection and subsequent transplant nephrectomy allowed discontinuation of corticosteroids, the gradual withdrawal of insulin and normoglycemia. The recent description of renal cysts and diabetes (RCAD) syndrome and a strong paternal family history of early-onset diabetes mellitus prompted genetic screening of the hepatocyte nuclear factor-1beta gene. A novel heterozygous frameshift mutation in exon 1 was identified, adding to the 12 kindreds thus far described. This case highlights the unmasking of the hyperglycemic component of the RCAD syndrome in the immediate postoperative period after renal transplantation and emphasizes the pleiotropic manifestations of this important genetic kidney disease.
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Affiliation(s)
- Simon C Waller
- Nephro-Urology Unit, Institute of Child Health, University College London and the Department of Diabetes and Vascular Medicine, School of Postgraduate Medicine and Health Sciences, University of Exeter, England.
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Pearson ER, Velho G, Clark P, Stride A, Shepherd M, Frayling TM, Bulman MP, Ellard S, Froguel P, Hattersley AT. beta-cell genes and diabetes: quantitative and qualitative differences in the pathophysiology of hepatic nuclear factor-1alpha and glucokinase mutations. Diabetes 2001; 50 Suppl 1:S101-7. [PMID: 11272165 DOI: 10.2337/diabetes.50.2007.s101] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Mutations in the beta-cell genes encoding the glycolytic enzyme glucokinase (GCK) and the transcription factor hepatocyte nuclear factor (HNF)-1alpha are the most common causes of maturity-onset diabetes of the young (MODY). Studying patients with mutations in these genes gives insights into the functions of these two critical beta-cell genes in humans. We studied 178 U.K. and French MODY family members, including 45 GCK mutation carriers and 40 HNF-1alpha mutation carriers. Homeostasis model assessment of fasting insulin and glucose showed reduced beta-cell function in both GCK (48% controls, P<0.0001) and HNF-1alpha (42% controls, P<0.0001). Insulin sensitivity was similar to that of control subjects in the GCK subjects (93% controls, P = 0.78) but increased in the HNF-1alpha subjects (134.5% controls, P = 0.005). The GCK patients showed a similar phenotype between and within families with mild lifelong fasting hyperglycemia (fasting plasma glucose [FPG] 5.5-9.2 mmol/l, interquartile [IQ] range 6.6-7.4), which declined slightly with age (0.017 mmol/l per year) and rarely required pharmacological treatment (17% oral hypoglycemic agents, 4% insulin). HNF-1alpha patients showed far greater variation in fasting glucose both between and within families (FPG 4.1-18.5 mmol/l, IQ range 5.45-10.4), with a marked deterioration with age (0.06 mmol/l per year), and 59% of patients required treatment with tablets or insulin. Proinsulin-to-insulin ratios are increased in HNF-1alpha subjects (29.5%) but not in GCK (18.5%) subjects. In an oral glucose tolerance test, the 0- to 120-min glucose increment was small in GCK patients (2.4+/-1.8 mmol/l) but large in HNF-1alpha patients (8.5+/-3.0 mmol/l, P< 0.0001). This comparison shows that the clear clinical differences in these two genetic subgroups of diabetes reflect the quantitative and qualitative differences in beta-cell dysfunction. The defect in GCK is a stable defect of glucose sensing, whereas the HNF-1alpha mutation causes a progressive defect that alters beta-cell insulin secretion directly rather than the sensing of glucose.
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Affiliation(s)
- E R Pearson
- Department of Vascular Medicine and Diabetes Research, School of Postgraduate Medicine and Health Sciences, University of Exeter, Devon, UK
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Pearson ER, Liddell WG, Shepherd M, Corrall RJ, Hattersley AT. Sensitivity to sulphonylureas in patients with hepatocyte nuclear factor-1alpha gene mutations: evidence for pharmacogenetics in diabetes. Diabet Med 2000; 17:543-5. [PMID: 10972586 DOI: 10.1046/j.1464-5491.2000.00305.x] [Citation(s) in RCA: 198] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Maturity-onset diabetes of the young (MODY) is characterized by autosomal dominantly inherited, early-onset, non-insulin-dependent diabetes. Mutations in the hepatocyte nuclear factor (HNF)-1alpha gene are the commonest cause of MODY. Individual patients with HNF-1alpha mutations have been reported as being unusually sensitive to the hypoglycaemic effects of sulphonylurea therapy. We report three patients, attending a single clinic, with HNF-1alpha mutations that show marked hypersensitivity to sulphonylureas. CASE REPORTS In cases 1 and 2 there were marked changes in HbA1c on cessation (4.4% and 5.8%, respectively) and reintroduction (5.0% and 2.6%) of sulphonylureas. Case 3 had severe hypoglycaemic symptoms on the introduction of sulphonylureas despite poor glycaemic control and was shown with a test dose of 2.5 mg glibenclamide to have symptomatic hypoglycaemia (blood glucose 2 mmol/l) after 4 h despite eating. CONCLUSIONS HNF-1alpha MODY diabetic subjects are more sensitive to sulphonylureas than Type 2 diabetic subjects and this is seen in different families, with different mutations and may continue up to 13 years from diagnosis. This is an example of pharmacogenetics, with the underlying aetiological genetic defect altering the pharmacological response to treatment. The present cases suggest that in HNF-1alpha MODY patients: (i) sulphonylureas can dramatically improve glycaemic control and should be considered as initial treatment for patients with poor glycaemic control on an appropriate diet; (ii) hypoglycaemia may complicate the introduction of sulphonylureas and therefore very low doses of short acting sulphonylureas should be used initially; and (iii) cessation of sulphonylureas should be undertaken cautiously as there may be marked deterioration in glycaemic control.
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Affiliation(s)
- E R Pearson
- Department of Diabetes and Vascular Medicine, School of Postgraduate Medicine and Health Sciences, University of Exeter, UK
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Pearson ER, Hattersley AT. Unravelling the heterogeneity of non insulin dependent diabetes. J R Coll Physicians Lond 2000; 34:332-5. [PMID: 11005066 PMCID: PMC9665487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
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Pearson ER, D'Souza RJ, Hamilton-Wood C, Nicholls AJ, Beaman M. Hypertensive encephalopathy and nephrotic syndrome: a possible link? Nephrol Dial Transplant 1999; 14:1750-2. [PMID: 10435888 DOI: 10.1093/ndt/14.7.1750] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- E R Pearson
- Renal Unit, Royal Devon and Exeter Hospital, Exeter, Devon, UK
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