Overfeeding during lactation induces change in GLUT4 and GLUT1 ratio and cardiac hypertrophy.

The study investigated the effects of early life overfeeding on metabolic alterations, heart morphology and left ventricular insulin signaling pathway, mainly the glucose transporters GLUT1, GLUT4 and pAKT/AKT ratio. Wistar rats were overfed using the litter size reduction method. The pups were studies at age of 10 and 21 days. We measured heart GLUT1, GLUT4, AKT and pAKT. Animal weight and length, total body lipid, glycogen content, and the plasma levels of insulin, glucose, total cholesterol and triglycerides were measured. Cardiac hypertrophy was evaluated by heart weight/tibia length ratio. Our results showed that overfed animals were overweight, displayed high total body lipids, insulin, glucose, cholesterol and triglycerides plasma levels, and left ventricular hypertrophy with increasing of pAKT/AKT ratio. Moreover, the heart of overfed animals displayed a precocious translocation of GLUT4 and decreased content of GLUT1. In conclusion, we suggest that overfeeding during lactation might induce metabolic and cardiac alterations early in life, leading to the development of cardiac hypertrophy due anticipated insulin dependence created by earlier GLUT4 heart appearance. [ABSTRACT FROM AUTHOR]