Insulin-like growth factor 1 (IGF-1) is a hormone similar in molecular structure to insulin but has a much higher growth-promoting activity IGF-1 consists of 70 amino acids in a single chain with three intramolecular disulfide bridges IGF-1 may be a physiological regulator of [1-14C]-2-deoxy-D-glucose (2DG) transport and glycogen synthesis in osteoblasts It is able to stimulate glucose transport in bone-derived osteoblastic (PyMS) cells and is effective at much lower concentrations than insulin not only regarding glycogen and DNA synthesis but also with regard to enhancing glucose uptake It may also play a role in synapse maturation