Gazzerro Elisabetta, Canalis Ernesto
a Dipartimento di Neuroscienze e Riabilitazione, Instituto Giannina, Gaslini, Genova, Italy.
b
Expert Rev Endocrinol Metab. 2006 Jan;1(1):47-56. doi: 10.1586/17446651.1.1.47.
Insulin-like growth factors (IGFs) promote longitudinal growth and display anabolic effects in adult bone by acting through endocrine and autocrine/paracrine mechanisms. Binding of IGF-I to its specific tyrosine-kinase receptor leads to interaction with the intracellular proteins, insulin receptor substrate-1 and -2, and the activation of distinct intracellular signaling pathways. In cartilage, IGF-I regulates the differentiation of chondrocytes and stimulates the synthesis of components of the extracellular matrix. In bone tissue, IGF-I increases the function of the differentiated osteoblasts and mediates selected anabolic actions of parathyroid hormone. Genetically modified mice, in which selected components of the IGF system were targeted in a tissue-specific fashion, have documented that circulating IGF-I is essential for physiological skeletal growth and adult bone remodeling and that local autocrine/paracrine IGF-I activities are required for optimal trabecular bone mass and mineralization. Studies in humans have indicated a correlation between serum IGF-I levels and bone mineral density. However, there is little information on the use of IGF-I in patients with metabolic bone disease.
胰岛素样生长因子（IGFs）通过内分泌和自分泌/旁分泌机制促进纵向生长，并在成年骨骼中发挥合成代谢作用。IGF-I与其特定的酪氨酸激酶受体结合会导致与细胞内蛋白质胰岛素受体底物-1和-2相互作用，并激活不同的细胞内信号通路。在软骨中，IGF-I调节软骨细胞的分化并刺激细胞外基质成分的合成。在骨组织中，IGF-I增强分化成骨细胞的功能，并介导甲状旁腺激素的某些合成代谢作用。以组织特异性方式靶向IGF系统特定成分的基因改造小鼠已证明，循环中的IGF-I对生理性骨骼生长和成年骨重塑至关重要，而局部自分泌/旁分泌IGF-I活性对于获得最佳骨小梁骨量和矿化是必需的。对人类的研究表明血清IGF-I水平与骨矿物质密度之间存在相关性。然而，关于IGF-I在代谢性骨病患者中的应用，相关信息很少。
