胎儿生长受限仔鼠脂肪组织中葡萄糖转运蛋白4的表达和细胞转位变化

Objective To investigate the effects of fetal growth restriction (FGR) on the expressions and translocation of glucose transporter 4 (GLUT4) in adipose tissue of male offsprings and its relationship with insulin resistance in FGR. Methods Male 8-week-old offspring from maternal with protein-malnutrition or normal diet were studied. The weight of rats at 8 weeks of age were obtained and insulin resistance index (IRI) was examined at 4 weeks and 8 weeks of age. Perinephric fat pads were harvested to measure the expression of GLUT4 mRNA by fluorescent quantitative RT-PCR and the GLUT4 protein level and insulin-stimulated transloeation were assessed by Western blot. Results Birth weight of FGR animals were significantly lower than that of control (t=6.399, P<0.01), but surpassed the control at 8 weeks with increased fasting IRI(P<0.05). The GLUT4 mRNA expression in adipose tissue of FGR rats (0.36± 0.04) was lower than that of control (1.01±0.11) (t=2.854, P<0.05). Declined total GLUT4 protein concentration(913.47±87.32) was also noted in the FGR group compared with the controls (1248.30± 131.52) (t=2.617, P<0.05). After administration of insulin, plasma membrane associated-GLUT4 concentration significantly increased to 897.03±102.87, which was equal to 2.12 times of the basal level (423.05±41.26) in control rats(t=4.759, P<0.01). However, insulin-responsive GLUT4 transloeation was markedly blunted in FGR rats(525.12±54.96) compared with controls, only increased to 1.38 times of the basal level (379.57±38.71)(t=2.083, P<0.05). Conclusions Decreased GLUT4 expression and insulin-stimulated translocation in adipose tissue of the male FGR offspring might be caused by exposure to protein malnutrition during pregnancy, which may disturb the uptake and utilization of glucose and subsequently be related to diabetes mellitus in later life.

Glucose transporter 4 expression and translocation in adipose tissue of male rats born with fetal growth restriction