Liver-derived IGF-I is of importance for normal carbohydrate and lipid metabolism

IGF-I is important for postnatal body growth and exhibits Insulin-like effe cts on carbohydrate metabolism. The function of liver-derived IGF-I is stil l not established, although we previously demonstrated that liver-derived I GF-I is not required for postnatal body growth, Mice whose IGF-I gene in th e liver was inactivated at 24 days of age were used to investigate the long -term role of liver-derived IGF-I for carbohydrate and lipid metabolism. Se rum levels of leptin in these mice were increased by >100% at 3 months of a ge, whereas the fat mass of the mice was decreased by 25% at 13 months of a ge. The mice became markedly hyperinsulinemic and yet normoglycemic, indica ting an adequately compensated insulin resistance. Furthermore, they had in creased serum levels of cholesterol, We conclude that; liver-derived IGF-I is of importance for carbohydrate and lipid metabolism.