Merlotti Daniela, Gennari Luigi, Stolakis Konstantinos, Nuti Ranuccio
Department of Internal Medicine, Endocrine-Metabolic Sciences and Biochemistry, Viale Bracci 1, 53100 Siena, Italy.
J Osteoporos. 2011;2011:230671. doi: 10.4061/2011/230671. Epub 2011 Jun 24.
Aromatase is a specific component of the cytochrome P450 enzyme system responsible for the transformation of androgen precursors into estrogens. This enzyme is encoded by the CYP19A1 gene located at chromosome 15q21.2, that is, expressed in ovary and testis, but also in many extraglandular sites such as the placenta, brain, adipose tissue, and bone. The activity of aromatase regulates the concentrations of estrogens with endocrine, paracrine, and autocrine effects on target issues including bone. Importantly, extraglandular aromatization of circulating androgen precursors is the major source of estrogen in men. Clinical and experimental evidences clearly indicate that aromatase activity and estrogen production are necessary for longitudinal bone growth, the attainment of peak bone mass, pubertal growth spurt, epiphyseal closure, and normal bone remodeling in young individuals. Moreover, with aging, individual differences in aromatase activity may significantly affect bone loss and fracture risk in men.
芳香化酶是细胞色素P450酶系统的一种特定成分，负责将雄激素前体转化为雌激素。该酶由位于染色体15q21.2的CYP19A1基因编码，即在卵巢和睾丸中表达，也在许多腺外部位如胎盘、大脑、脂肪组织和骨骼中表达。芳香化酶的活性调节雌激素浓度，对包括骨骼在内的靶组织具有内分泌、旁分泌和自分泌作用。重要的是，循环雄激素前体的腺外芳香化是男性雌激素的主要来源。临床和实验证据清楚地表明，芳香化酶活性和雌激素产生对于纵向骨生长、峰值骨量的获得、青春期生长突增、骨骺闭合以及年轻个体正常的骨重塑是必需的。此外，随着年龄增长，芳香化酶活性的个体差异可能会显著影响男性的骨质流失和骨折风险。
