Department of Biomedical Sciences and Human Oncology, University of Bari, Piazza G. Cesare 11, 70124 Bari, Italy.
Biomed Res Int. 2013;2013:250462. doi: 10.1155/2013/250462. Epub 2013 Jan 8.
21-Hydroxylase deficiency (21-OHD) is the most common cause of congenital adrenal hyperplasia (CAH), resulting from deletions or mutations of the P450 21-hydroxylase gene (CYP21A2). Children with 21-OHD need chronic glucocorticoid (cGC) therapy, both to replace congenital deficit in cortisol synthesis and to reduce androgen secretion by adrenal cortex. GC-induced osteoporosis (GIO) is the most common form of secondary osteoporosis that results in an early, transient increase in bone resorption accompanied by a decrease in bone formation, maintained for the duration of GC therapy. Despite the conflicting results in the literature about the bone status on GC-treated patients with 21-OHD, many reports consider these subjects to be at risk for osteoporosis and fractures. In bone cells, at the molecular level, GCs regulate various functions including osteoblastogenesis, osteoclastogenesis, and the apoptosis of osteoblasts and osteocytes. In this paper, we focus on the physiology and biosynthesis of endogenous steroid hormones as well as on the effects of GCs on bone cells, highlighting the pathogenetic mechanism of GIO in children with 21-OHD.
21-羟化酶缺乏症（21-OHD）是先天性肾上腺皮质增生症（CAH）最常见的原因，是由于 P450 21-羟化酶基因（CYP21A2）的缺失或突变引起的。21-OHD 患儿需要长期接受糖皮质激素（GC）治疗，不仅要替代先天性皮质醇合成不足，还要减少肾上腺皮质分泌雄激素。GC 诱导的骨质疏松症（GIO）是最常见的继发性骨质疏松症，导致骨吸收早期、短暂增加，同时骨形成减少，GC 治疗期间持续存在。尽管文献中关于 21-OHD 患儿 GC 治疗患者的骨骼状况存在相互矛盾的结果，但许多报告认为这些患者存在骨质疏松症和骨折的风险。在骨细胞中，GC 在分子水平上调节各种功能，包括成骨细胞生成、破骨细胞生成以及成骨细胞和骨细胞的凋亡。在本文中，我们重点关注内源性甾体激素的生理学和生物合成，以及 GC 对骨细胞的影响，突出了 21-OHD 患儿 GIO 的发病机制。
