GH and IGF-I are important regulators of bone homeostasis and are central to the achievement of normal longitudinal bone growth and bone mass. Although GH may act directly on skeletal cells, most of its effects are mediated by IGF-I, which is present in the systemic circulation and is synthesized by peripheral tissues. The availability of IGF-I is regulated by IGF binding proteins. IGF-I enhances the differentiated function of the osteoblast and bone formation. Adult GH deficiency causes low bone turnover osteoporosis with high risk of vertebral and nonvertebral fractures, and the low bone mass can be partially reversed by GH replacement. Acromegaly is characterized by high bone turnover, which can lead to bone loss and vertebral fractures, particularly in patients with coexistent hypogonadism. GH and IGF-I secretion are decreased in aging individuals, and abnormalities in the GH/IGF-I axis play a role in the pathogenesis of the osteoporosis of anorexia nervosa and after glucocorticoid exposure.

中文翻译：

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生长激素、胰岛素样生长因子和骨骼。


GH 和 IGF-I 是骨稳态的重要调节剂，对于实现正常的纵向骨生长和骨量至关重要。虽然 GH 可能直接作用于骨骼细胞，但其大部分作用是由 IGF-I 介导的，IGF-I 存在于体循环中，由外周组织合成。 IGF-I 的可用性受 IGF 结合蛋白的调节。 IGF-I增强成骨细胞的分化功能和骨形成。成人 GH 缺乏会导致低骨转换骨质疏松症，并伴有椎体和非椎体骨折的高风险，而低骨量可以通过 GH 替代来部分逆转。肢端肥大症的特点是骨转换率高，这可能导致骨质流失和椎骨骨折，特别是对于同时存在性腺功能减退症的患者。衰老个体中 GH 和 IGF-I 分泌减少，GH/IGF-I 轴异常在神经性厌食症和糖皮质激素暴露后骨质疏松症的发病机制中发挥作用。