No detectable effect of a type 2 diabetes-associated TCF7L2 genotype on the incretin effect

David S Mathiesen, Jonatan I Bagger, Katrine Bagge Hansen, Anders E Junker, Astrid Plamboeck, Signe Harring, Thomas Idorn, Mads Hornum, Jens J Holst, Anna E Jonsson, Torben Hansen, Tina Vilsbøll, Asger Lund, Filip K Knop

2 Citations (Scopus)

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.

Original languageEnglish
JournalEndocrine Connections
Volume9
Issue number12
Pages (from-to)1221-1232
Number of pages12
ISSN2049-3614
DOIs
Publication statusPublished - Dec 2020

Keywords

  • SNP
  • TCF7L2
  • incretin effect
  • incretins
  • transcription factor 7-like 2
  • type 2 diabetes
  • Incretins
  • Type 2 diabetes
  • Transcription factor 7-like 2
  • Incretin effect

Fingerprint

Dive into the research topics of 'No detectable effect of a type 2 diabetes-associated TCF7L2 genotype on the incretin effect'. Together they form a unique fingerprint.

Cite this