Transient Congenital Hypothyroidism Alters Gene Expression of Glucose Transporters and Impairs Glucose Sensing Apparatus in Young and Aged Offspring Rats

Cell Physiol Biochem. 2017;43(6):2338-2352. doi: 10.1159/000484386. Epub 2017 Oct 27.

Abstract

Background/aims: Transient congenital hypothyroidism (TCH) could disturb carbohydrate metabolism in adulthood. Aging is associated with increased risk of type 2 diabetes. This study aims to address effects of TCH on mRNA expressions of glucose transporters (GLUTs) and glucokinase (GcK) in islets and insulin target tissues of aged offspring rats.

Methods: The TCH group received water containing 0.025% 6-propyl-2-thiouracil during gestation. Offspring from control and TCH groups (n=6 in each group) were followed until month 19. Gene expressions of GLUTs and GcK were measured at months 3 and 19.

Results: Compared to controls, aged TCH rats had higher GLUT4 expression in heart (4.88 fold) and soleus (6.91 fold), while expression was lower in epididymal fat (12%). In TCH rats, GLUT2 and GcK expressions in islets were lower in young (12% and 10%, respectively) and higher in aged (10.85 and 8.42 fold, respectively) rats. In addition, liver GLUT2 and GcK expressions were higher in young (13.11 and 21.15 fold, respectively) and lower in aged rats (44% and 5%, respectively).

Conclusion: Thyroid hormone deficiency during fetal period impaired glucose sensing apparatus and changed glucose transporter expression in insulin-sensitive tissues of aged offspring rats. These changes may contribute to impaired carbohydrate metabolism.

Keywords: Carbohydrate metabolism; Glucose transporter; Insulin; Rat; Transient congenital hypothyroidism.

MeSH terms

  • Aging*
  • Animals
  • Blood Glucose / analysis
  • Body Weight
  • Congenital Hypothyroidism / metabolism
  • Congenital Hypothyroidism / pathology*
  • Congenital Hypothyroidism / veterinary
  • Glucokinase / genetics
  • Glucokinase / metabolism
  • Glucose Tolerance Test
  • Glucose Transporter Type 1 / genetics
  • Glucose Transporter Type 1 / metabolism*
  • Glucose Transporter Type 2 / genetics
  • Glucose Transporter Type 2 / metabolism*
  • Glucose Transporter Type 4 / genetics
  • Glucose Transporter Type 4 / metabolism*
  • Insulin / analysis
  • Islets of Langerhans / metabolism
  • Liver / metabolism
  • Male
  • Myocardium / metabolism
  • RNA, Messenger / metabolism
  • Rats
  • Rats, Wistar
  • Thyrotropin / blood
  • Thyroxine / blood
  • Transcriptome
  • Triiodothyronine / blood

Substances

  • Blood Glucose
  • Glucose Transporter Type 1
  • Glucose Transporter Type 2
  • Glucose Transporter Type 4
  • Insulin
  • RNA, Messenger
  • Triiodothyronine
  • Thyrotropin
  • Glucokinase
  • Thyroxine