320 ALTERATIONS IN AKT PHOSPHORYLATION IN EXERCISE TRAINED INTRAUTERINE GROWTH RESTRICTED RATS

Intrauterine growth restriction (IUGR) leads to dysregulation of glucose/insulin homeostasis and aberrant Glut4 translocation. Alterations in the Glut4 translocation pathway due to IUGR are not clearly elucidated, and it is unclear whether exercise can help reverse alterations. Phosphorylation of Akt (pAkt) is a part of the Glut4 translocation pathway. We assessed pAkt and insulin-induced Glut4 translocation in control (n=6) and maternal nutrient restriction induced IUGR (n=6) rats. Rats were exercised 15min/day from day21 to day60 or allowed to remain sedentary. Skeletal muscle was obtained at day 2 and 60, and proteins of interest were assessed by Western blot. At day 2, insulin administration led to increased Glut4 translocation in control rats, but not in IUGR rats. At day 60, insulin increased pAkt levels in control and IUGR rats, but significantly increased Glut4 translocation in control rats (p≤0.05), but not in IUGR rats. After exercise, insulin administration increased pAkt in control and IUGR rats, and insulin-induced Glut4 translocation was significantly increased in both control and IUGR groups (p≤0.05). We conclude that exercise is beneficial in IUGR rats since it increases insulin sensitivity of the insulin-GLUT 4 translocation pathway.