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Galderisi A, Tricò D, Lat J, Samuels S, Weiss R, Van Name M, Pierpont B, Santoro N, Caprio S. Incretin effect determines glucose trajectory and insulin sensitivity in youths with obesity. JCI Insight 2023; 8:e165709. [PMID: 37847560 PMCID: PMC10721315 DOI: 10.1172/jci.insight.165709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 10/11/2023] [Indexed: 10/18/2023] Open
Abstract
In youths with obesity, the gut hormone potentiation of insulin secretion - the incretin effect - is blunted. We explored the longitudinal impact of the incretin effect during pubertal transition on β cell function and insulin sensitivity. Youths with obesity and 2-hour glucose level ≥ 120 mg/dL underwent a 3-hour oral glucose-tolerance test (OGTT) and an isoglycemic i.v. glucose infusion to quantify the incretin effect. After 2 years, 30 of 39 participants had a repeated OGTT and were stratified into 3 tertiles according to the baseline incretin effect. The high-incretin effect group demonstrated a longitudinal increase in β cell function (disposition index, minimal model [DIMM]), with greater insulin sensitivity at follow-up and stable insulin secretion (φtotal). A lower incretin effect at baseline was associated with higher 1-hour and 2-hour glucose level at follow-up. The high-incretin effect group displayed a greater increase of GLP-17-36 than the moderate- and low-incretin group at baseline, while such a difference did not persist after 2 years. Glucagon suppression was reduced at follow-up in those with low-baseline incretin in respect to the high-incretin group. The incretin effect during pubertal transition affected the longitudinal trajectory of β cell function and weight in youths with obesity.
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Affiliation(s)
- Alfonso Galderisi
- Yale University, Department of Pediatrics, New Haven, Connecticut, USA
| | - Domenico Tricò
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Jessica Lat
- Yale University, Department of Pediatrics, New Haven, Connecticut, USA
| | - Stephanie Samuels
- Yale University, Department of Pediatrics, New Haven, Connecticut, USA
| | - Ram Weiss
- Department of Pediatrics, Ruth Rappaport Childrens’ Hospital, Rambam Medical Center, Haifa, Israel
| | - Michelle Van Name
- Yale University, Department of Pediatrics, New Haven, Connecticut, USA
| | - Bridget Pierpont
- Yale University, Department of Pediatrics, New Haven, Connecticut, USA
| | - Nicola Santoro
- Yale University, Department of Pediatrics, New Haven, Connecticut, USA
- Department of Medicine and Health Sciences University of Molise, Campobasso, Italy
| | - Sonia Caprio
- Yale University, Department of Pediatrics, New Haven, Connecticut, USA
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Niu M, Zhao Y, Jia Y, Xiang L, Dai X, Chen H. Whole-genome sequencing study to identify candidate markers indicating susceptibility to type 2 diabetes in Bama miniature pigs. Animal Model Exp Med 2023; 6:283-293. [PMID: 37132291 PMCID: PMC10486338 DOI: 10.1002/ame2.12317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Accepted: 03/08/2023] [Indexed: 05/04/2023] Open
Abstract
BACKGROUND Hundreds of single-nucleotide polymorphism (SNP) sites have been found to be potential genetic markers of type 2 diabetes mellitus (T2DM). However, SNPs related to T2DM in minipigs have been less reported. This study aimed to screen the T2DM-susceptible candidate SNP loci in Bama minipigs so as to improve the success rate of the minipig T2DM model. METHODS The genomic DNAs of three Bama minipigs with T2DM, six sibling low-susceptibility minipigs with T2DM, and three normal control minipigs were compared by whole-genome sequencing. The T2DM Bama minipig-specific loci were obtained, and their functions were annotated. Meanwhile, the Biomart software was used to perform homology alignment with T2DM-related loci obtained from the human genome-wide association study to screen candidate SNP markers for T2DM in Bama miniature pigs. RESULTS Whole-genome resequencing detected 6960 specific loci in the minipigs with T2DM, and 13 loci corresponding to 9 diabetes-related genes were selected. Further, a set of 122 specific loci in 69 orthologous genes of human T2DM candidate genes were obtained in the pigs. Collectively, a batch of T2DM-susceptible candidate SNP markers in Bama minipigs, covering 16 genes and 135 loci, was established. CONCLUSIONS Whole-genome sequencing and comparative genomics analysis of the orthologous genes in pigs that corresponded to the human T2DM-related variant loci successfully screened out T2DM-susceptible candidate markers in Bama miniature pigs. Using these loci to predict the susceptibility of the pigs before constructing an animal model of T2DM may help to establish an ideal animal model.
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Affiliation(s)
- Miaomiao Niu
- Laboratory Animal CenterChinese PLA General HospitalBeijingPR China
| | - Yuqiong Zhao
- Laboratory Animal CenterChinese PLA General HospitalBeijingPR China
| | - Yunxiao Jia
- Laboratory Animal CenterChinese PLA General HospitalBeijingPR China
| | - Lei Xiang
- Beijing Institute of Orthopaedic TraumaBeijing Jishuitan HospitalBeijingPR China
| | - Xin Dai
- Laboratory Animal CenterChinese PLA General HospitalBeijingPR China
| | - Hua Chen
- Laboratory Animal CenterChinese PLA General HospitalBeijingPR China
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Azarova I, Polonikov A, Klyosova E. Molecular Genetics of Abnormal Redox Homeostasis in Type 2 Diabetes Mellitus. Int J Mol Sci 2023; 24:ijms24054738. [PMID: 36902173 PMCID: PMC10003739 DOI: 10.3390/ijms24054738] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 02/20/2023] [Accepted: 02/24/2023] [Indexed: 03/05/2023] Open
Abstract
Numerous studies have shown that oxidative stress resulting from an imbalance between the production of free radicals and their neutralization by antioxidant enzymes is one of the major pathological disorders underlying the development and progression of type 2 diabetes (T2D). The present review summarizes the current state of the art advances in understanding the role of abnormal redox homeostasis in the molecular mechanisms of T2D and provides comprehensive information on the characteristics and biological functions of antioxidant and oxidative enzymes, as well as discusses genetic studies conducted so far in order to investigate the contribution of polymorphisms in genes encoding redox state-regulating enzymes to the disease pathogenesis.
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Affiliation(s)
- Iuliia Azarova
- Department of Biological Chemistry, Kursk State Medical University, 3 Karl Marx Street, 305041 Kursk, Russia
- Laboratory of Biochemical Genetics and Metabolomics, Research Institute for Genetic and Molecular Epidemiology, Kursk State Medical University, 18 Yamskaya Street, 305041 Kursk, Russia
| | - Alexey Polonikov
- Laboratory of Statistical Genetics and Bioinformatics, Research Institute for Genetic and Molecular Epidemiology, Kursk State Medical University, 18 Yamskaya Street, 305041 Kursk, Russia
- Department of Biology, Medical Genetics and Ecology, Kursk State Medical University, 3 Karl Marx Street, 305041 Kursk, Russia
- Correspondence:
| | - Elena Klyosova
- Laboratory of Biochemical Genetics and Metabolomics, Research Institute for Genetic and Molecular Epidemiology, Kursk State Medical University, 18 Yamskaya Street, 305041 Kursk, Russia
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Tricò D, McCollum S, Samuels S, Santoro N, Galderisi A, Groop L, Caprio S, Shabanova V. Mechanistic Insights Into the Heterogeneity of Glucose Response Classes in Youths With Obesity: A Latent Class Trajectory Approach. Diabetes Care 2022; 45:1841-1851. [PMID: 35766976 PMCID: PMC9346992 DOI: 10.2337/dc22-0110] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 05/03/2022] [Indexed: 02/03/2023]
Abstract
OBJECTIVE In a large, multiethnic cohort of youths with obesity, we analyzed pathophysiological and genetic mechanisms underlying variations in plasma glucose responses to a 180 min oral glucose tolerance test (OGTT). RESEARCH DESIGN AND METHODS Latent class trajectory analysis was used to identify various glucose response profiles to a nine-point OGTT in 2,378 participants in the Yale Pathogenesis of Youth-Onset T2D study, of whom 1,190 had available TCF7L2 genotyping and 358 had multiple OGTTs over a 5 year follow-up. Insulin sensitivity, clearance, and β-cell function were estimated by glucose, insulin, and C-peptide modeling. RESULTS Four latent classes (1 to 4) were identified based on increasing areas under the curve for glucose. Participants in class 3 and 4 had the worst metabolic and genetic risk profiles, featuring impaired insulin sensitivity, clearance, and β-cell function. Model-predicted probability to be classified as class 1 and 4 increased across ages, while insulin sensitivity and clearance showed transient reductions and β-cell function progressively declined. Insulin sensitivity was the strongest determinant of class assignment at enrollment and of the longitudinal change from class 1 and 2 to higher classes. Transitions between classes 3 and 4 were explained only by changes in β-cell glucose sensitivity. CONCLUSIONS We identified four glucose response classes in youths with obesity with different genetic risk profiles and progressive impairment in insulin kinetics and action. Insulin sensitivity was the main determinant in the transition between lower and higher glucose classes across ages. In contrast, transitions between the two worst glucose classes were driven only by β-cell glucose sensitivity.
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Affiliation(s)
- Domenico Tricò
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Sarah McCollum
- Department of Pediatrics, Yale University School of Medicine, New Haven, CT
| | - Stephanie Samuels
- Department of Pediatrics, Yale University School of Medicine, New Haven, CT
| | - Nicola Santoro
- Department of Pediatrics, Yale University School of Medicine, New Haven, CT.,Department of Medicine and Health Sciences, "V. Tiberio" University of Molise, Campobasso, Italy
| | - Alfonso Galderisi
- Pediatric Endocrinology, Hôpital Necker-Enfants Malades, Paris, France
| | - Leif Groop
- Department of Clinical Sciences, Genomics, Diabetes and Endocrinology, Lund University, Malmö, Sweden
| | - Sonia Caprio
- Department of Pediatrics, Yale University School of Medicine, New Haven, CT
| | - Veronika Shabanova
- Department of Pediatrics, Yale University School of Medicine, New Haven, CT
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Grespan E, Guolo A, Muscelli E, Ferrannini E, Mari A. Loss of the Incretin Effect in Type 2 Diabetes: A Systematic Review and Meta-analysis. J Clin Endocrinol Metab 2022; 107:2092-2100. [PMID: 35397169 DOI: 10.1210/clinem/dgac213] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Indexed: 11/19/2022]
Abstract
CONTEXT Loss of the incretin effect (IE) in type 2 diabetes (T2D) contributes to hyperglycemia and the mechanisms underlying this impairment are unclear. OBJECTIVE To quantify the IE impairment in T2D and to investigate the factors associated with it using a meta-analytic approach. METHODS PubMed, Scopus, and Web-of-Science were searched. Studies measuring IE by the gold-standard protocol employing an oral glucose tolerance test (OGTT) and an intravenous glucose infusion at matched glucose levels were selected. We extracted IE, sex, age, body mass index (BMI), and hemoglobin A1c, fasting values, and area under curve (AUC) of glucose, insulin, C-peptide, glucose-dependent insulinotropic peptide (GIP) and glucagon-like peptide 1 (GLP-1). In subjects with T2D, we also recorded T2D duration, age at diagnosis, and the percentage of subjects taking antidiabetic medications. RESULTS The IE weighted mean difference between subjects with T2D and those with normal glucose tolerance (NGT) was -27.3% (CI -36.5% to -18.1%; P < .001; I2 = 86.6%) and was affected by age (P < .005). By meta-regression of combined NGT and T2D data, IE was inversely associated with glucose tolerance (lower IE in T2D), BMI, and fasting GIP (P < .05). By meta-regression of T2D studies only, IE was associated with the OGTT glucose dose (P < .0001). IE from insulin was larger than IE from C-peptide (weighted mean difference 11.2%, CI 9.2-13.2%; P < .0001; I2 = 28.1%); the IE difference was inversely associated with glucose tolerance and fasting glucose. CONCLUSION The IE impairment in T2D vs NGT is consistent though considerably variable, age being a possible factor affecting the IE difference. Glucose tolerance, BMI, and fasting GIP are independently associated with IE; in subjects with T2D only, the OGTT dose is a significant covariate.
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Affiliation(s)
| | - Annamaria Guolo
- Department of Statistical Sciences, University of Padua, Padua, Italy
| | - Elza Muscelli
- Department of Internal Medicine, School of Medical Sciences, State University of Campinas, Campinas, Brazil
| | | | - Andrea Mari
- C.N.R. Institute of Neuroscience, Padua, Italy
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Molecular Mechanism of Pancreatic β-Cell Failure in Type 2 Diabetes Mellitus. Biomedicines 2022; 10:biomedicines10040818. [PMID: 35453568 PMCID: PMC9030375 DOI: 10.3390/biomedicines10040818] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Revised: 03/27/2022] [Accepted: 03/29/2022] [Indexed: 02/08/2023] Open
Abstract
Various important transcription factors in the pancreas are involved in the process of pancreas development, the differentiation of endocrine progenitor cells into mature insulin-producing pancreatic β-cells and the preservation of mature β-cell function. However, when β-cells are continuously exposed to a high glucose concentration for a long period of time, the expression levels of several insulin gene transcription factors are substantially suppressed, which finally leads to pancreatic β-cell failure found in type 2 diabetes mellitus. Here we show the possible underlying pathway for β-cell failure. It is likely that reduced expression levels of MafA and PDX-1 and/or incretin receptor in β-cells are closely associated with β-cell failure in type 2 diabetes mellitus. Additionally, since incretin receptor expression is reduced in the advanced stage of diabetes mellitus, incretin-based medicines show more favorable effects against β-cell failure, especially in the early stage of diabetes mellitus compared to the advanced stage. On the other hand, many subjects have recently suffered from life-threatening coronavirus infection, and coronavirus infection has brought about a new and persistent pandemic. Additionally, the spread of coronavirus infection has led to various limitations on the activities of daily life and has restricted economic development worldwide. It has been reported recently that SARS-CoV-2 directly infects β-cells through neuropilin-1, leading to apoptotic β-cell death and a reduction in insulin secretion. In this review article, we feature a possible molecular mechanism for pancreatic β-cell failure, which is often observed in type 2 diabetes mellitus. Finally, we are hopeful that coronavirus infection will decline and normal daily life will soon resume all over the world.
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Redondo MJ, Warnock MV, Libman IM, Bocchino LE, Cuthbertson D, Geyer S, Pugliese A, Steck AK, Evans-Molina C, Becker D, Sosenko JM, Bacha F. TCF7L2 Genetic Variants Do Not Influence Insulin Sensitivity or Secretion Indices in Autoantibody-Positive Individuals at Risk for Type 1 Diabetes. Diabetes Care 2021; 44:2039-2044. [PMID: 34326068 PMCID: PMC8740915 DOI: 10.2337/dc21-0531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 06/10/2021] [Indexed: 02/03/2023]
Abstract
OBJECTIVE We aimed to test whether type 2 diabetes (T2D)-associated TCF7L2 genetic variants affect insulin sensitivity or secretion in autoantibody-positive relatives at risk for type 1 diabetes (T1D). RESEARCH DESIGN AND METHODS We studied autoantibody-positive TrialNet Pathway to Prevention study participants (N = 1,061) (mean age 16.3 years) with TCF7L2 single nucleotide polymorphism (SNP) information and baseline oral glucose tolerance test (OGTT) to calculate indices of insulin sensitivity and secretion. With Bonferroni correction for multiple comparisons, P values < 0.0086 were considered statistically significant. RESULTS None, one, and two T2D-linked TCF7L2 alleles were present in 48.1%, 43.9%, and 8.0% of the participants, respectively. Insulin sensitivity (as reflected by 1/fasting insulin [1/IF]) decreased with increasing BMI z score and was lower in Hispanics. Insulin secretion (as measured by 30-min C-peptide index) positively correlated with age and BMI z score. Oral disposition index was negatively correlated with age, BMI z score, and Hispanic ethnicity. None of the indices were associated with TCF7L2 SNPs. In multivariable analysis models with age, BMI z score, ethnicity, sex, and TCF7L2 alleles as independent variables, C-peptide index increased with age, while BMI z score was associated with higher insulin secretion (C-peptide index), lower insulin sensitivity (1/IF), and lower disposition index; there was no significant effect of TCF7L2 SNPs on any of these indices. When restricting the analyses to participants with a normal OGTT (n = 743; 70%), the results were similar. CONCLUSIONS In nondiabetic autoantibody-positive individuals, TCF7L2 SNPs were not related to insulin sensitivity or secretion indices after accounting for BMI z score, age, sex, and ethnicity.
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Affiliation(s)
- Maria J Redondo
- Texas Children's Hospital, Baylor College of Medicine, Houston, TX
| | | | | | - Laura E Bocchino
- University of South Florida, Tampa, FL.,Jaeb Center for Health Research, Tampa, FL
| | | | - Susan Geyer
- University of South Florida, Tampa, FL.,Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN
| | | | - Andrea K Steck
- Barbara Davis Center for Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Carmella Evans-Molina
- Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, IN
| | | | - Jay M Sosenko
- Diabetes Research Institute, Miller School of Medicine, University of Miami, Miami, FL
| | - Fida Bacha
- Texas Children's Hospital, Baylor College of Medicine, Houston, TX.,Children's Nutrition Research Center, Agricultural Research Service, U.S. Department of Agriculture, Houston, TX
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Dietary Macronutrient Intake May Influence the Effects of TCF7L2 rs7901695 Genetic Variants on Glucose Homeostasis and Obesity-Related Parameters: A Cross-Sectional Population-Based Study. Nutrients 2021; 13:nu13061936. [PMID: 34200102 PMCID: PMC8230266 DOI: 10.3390/nu13061936] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 05/28/2021] [Accepted: 06/04/2021] [Indexed: 01/07/2023] Open
Abstract
Transcription factor-7–like 2 (TCF7L2) is one of the most important susceptibility genes for type 2 diabetes mellitus (T2DM). The aim of our cross-sectional population-based study was to analyze whether daily macronutrient intake may influence the effects of the TCF7L2 rs7901695 genotype on glucose homeostasis and obesity-related parameters. We recruited 810 participants (47.5% men and 52.5% women), 18–79 years old (mean age, 42.1 (±14.5) years), who were genotyped for the common TCF7L2 rs7901695 single-nucleotide polymorphism (SNP), and anthropometric measurements, body composition, body fat distribution (visceral (VAT) and subcutaneous adipose tissue (SAT) content), blood glucose and insulin concentrations after fasting and during OGTTs, and HbA1c were assessed. The VAT/SAT ratio, HOMA-IR (homeostatic model assessment of insulin resistance), HOMA-B (homeostatic model assessment of β-cell function), and CIR30 (corrected insulin response) were calculated. The daily macronutrient intake was evaluated based on 3-day food-intake diaries. Daily physical activity was evaluated based on a validated questionnaire. We performed ANOVA or Kruskal–Wallis tests, and multivariate linear regression models were created to evaluate the effects of dietary macronutrient intake on glucose homeostasis and obesity-related parameters in carriers of the investigated genotypes. This study was registered at ClinicalTrials.gov as NCT03792685. The TT-genotype carriers stratified to the upper protein intake quantiles presented higher HbA1c levels than the CT- and CC-genotype participants in the same quantiles (p = 0.038 and p = 0.022, respectively). Moreover, we observed higher HOMA-IR (p = 0.014), as well as significantly higher blood glucose and insulin concentrations, during the OGTTs for those in the upper quantiles, when compared to subjects from the lower quantiles of protein intake, while the CC-genotype carriers presented significantly lower HbA1c (p = 0.033) and significantly higher CIR30 (p = 0.03). The linear regression models revealed that an increase in energy derived from proteins in TT carriers was associated with higher HbA1c levels (β = 0.37 (95% CI: 0.01–0.74, p = 0.05)), although, in general, carrying the TT genotype, but without considering protein intake, showed an opposite tendency—to lower HbA1c levels (β = −0.22 (95% CI: 0.47 to −0.01, p = 0.05). Among the subjects stratified to the lower quantile of carbohydrate intake, the TT-genotype individuals presented higher HbA1c (p = 0.041), and the CC-genotype subjects presented higher VAT (p = 0.033), lower SAT (p = 0.033), and higher VAT/SAT ratios (p = 0.034). In both the CC- and TT-genotype carriers, we noted higher VAT (p = 0.012 and p = 0.0006, respectively), lower SAT (p = 0.012 and p = 0.0006, respectively) and higher VAT/SAT ratios (p = 0.016 and p = 0.00062, respectively) when dietary fat provided more than 30% of total daily energy intake, without any differences in total body fat content. Our findings suggest that associations of the common TCF7L2 SNP with glucose homeostasis and obesity-related parameters may be dependent on daily macronutrient intake, which warrants further investigations in a larger population, as well as interventional studies.
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Mathiesen DS, Bagger JI, Hansen KB, Junker AE, Plamboeck A, Harring S, Idorn T, Hornum M, Holst JJ, Jonsson AE, Hansen T, Vilsbøll T, Lund A, Knop FK. No detectable effect of a type 2 diabetes-associated TCF7L2 genotype on the incretin effect. Endocr Connect 2020; 9:1221-1232. [PMID: 33252353 PMCID: PMC7774769 DOI: 10.1530/ec-20-0471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 11/02/2020] [Indexed: 11/25/2022]
Abstract
The T allele of TCF7L2 rs7903146 is a common genetic variant associated with type 2 diabetes (T2D), possibly by modulation of incretin action. In this study, we evaluated the effect of the TCF7L2 rs7903146 T allele on the incretin effect and other glucometabolic parameters in normal glucose tolerant individuals (NGT) and participants with T2D. The rs7903146 variant was genotyped in cohorts of 61 NGT individuals (23 were heterozygous (CT) or homozygous (TT) T allele carriers) and 43 participants with T2D (20 with CT/TT). Participants were previously examined by an oral glucose tolerance test (OGTT) and a subsequent isoglycemic intravenous glucose infusion (IIGI). The incretin effect was assessed by quantification of the difference in integrated beta cell secretory responses during the OGTT and IIGI. Glucose and hormonal levels were measured during experimental days, and from these, indices of beta cell function and insulin sensitivity were calculated. No genotype-specific differences in the incretin effect were observed in the NGT group (P = 0.70) or the T2D group (P = 0.68). NGT T allele carriers displayed diminished glucose-dependent insulinotropic polypeptide response during OGTT (P = 0.01) while T allele carriers with T2D were characterized by lower C-peptide AUC after OGTT (P = 0.04) and elevated glucose AUC after OGTT (P = 0.04). In conclusion, our findings do not exclude that this specific TCF7L2 variant increases the risk of developing T2D via diminished incretin effect, but genotype-related defects were not detectable in these cohorts.
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Affiliation(s)
- David S Mathiesen
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
| | - Jonatan I Bagger
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
- Steno Diabetes Center Copenhagen, Gentofte, Denmark
- Department of Medicine, Gentofte and Herlev Hospital, University of Copenhagen, Denmark
| | - Katrine B Hansen
- Department of Medicine, Gentofte and Herlev Hospital, University of Copenhagen, Denmark
| | | | - Astrid Plamboeck
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Signe Harring
- Department of Gastroenterology, Hvidovre Hospital, University of Copenhagen, Hvidovre, Denmark
| | - Thomas Idorn
- Center for Cancer and Organ Diseases, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Mads Hornum
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Center for Cancer and Organ Diseases, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
- Department of Medicine, Gentofte and Herlev Hospital, University of Copenhagen, Denmark
| | | | | | | | - Tina Vilsbøll
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
- Novartis Healthcare A/S, Copenhagen, Denmark
- Department of Nephrology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Asger Lund
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Filip K Knop
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
- Novartis Healthcare A/S, Copenhagen, Denmark
- Department of Nephrology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Medicine, Gentofte and Herlev Hospital, University of Copenhagen, Denmark
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