Insulin-like growth factor-1 (IGF-1) is a polypeptide neurotrophic factor. Under the physiological condition, IGF-1 and its receptor are widely distributed in the central nervous system, and under the pathologic condition, the expression of IGF-1 is upregulated. IGF-1 inhibits cell apoptosis, regulates ion channel activity and inhibits the nitric oxide toxicity via mitogen-activated protein kinase and phosphatidyl inositol 3 kinase /serine-threonine protein kinase signaling pathways, thus exerts neuroprotective effects.