Wang Qingju, Alén Markku, Nicholson Patrick H F, Halleen Jussi M, Alatalo Sari L, Ohlsson Claes, Suominen Harri, Cheng Sulin
Department of Health Sciences, University of Jyväskylä, P.O. Box 35 (LL), FIN-40014, Jyväskylä, Finland.
J Clin Endocrinol Metab. 2006 Jan;91(1):277-82. doi: 10.1210/jc.2005-1608. Epub 2005 Oct 25.
The role of sex steroids in bone growth in pubertal girls is not yet clear. Bone biomarkers are indicators of bone metabolic activity, but their value in predicting bone quality has not been studied in growing girls.
This study examines the association of sex hormones and bone markers with bone geometry and density in pubertal girls.
The study was designed as a 2-yr longitudinal study in pubertal girls. Measurements were performed at baseline and at 1- and 2-yr follow-ups.
The study was conducted in a university laboratory.
A total of 258 10- to 13-yr-old healthy girls at the baseline participated.
Peripheral quantitative computed tomography was used to scan the left tibial shaft. Serum 17beta-estradiol (E2), testosterone (T), SHBG, osteocalcin (OC), bone-specific alkaline phosphatase, and tartrate-resistant acid phosphatase isoform 5b were assessed. Data were analyzed using hierarchical linear models with random effect.
E2 was a positive predictor for total bone mineral density (BMD), cortical thickness, and a negative predictor for endocortical circumference but had no predictive value for total bone cross-sectional area or periosteal circumference. T was a positive predictor for total cross-sectional area and periosteal circumference as well as endocortical circumference, and a negative predictor for total BMD. OC was negatively correlated with cortical BMD (R2 = 0.325; P < 0.001).
In pubertal girls, E2 and T have different influences on bone properties at the long bone shaft. The results suggest that, at the endocortical surface, E2 inhibits bone resorption during rapid growth, and later, after menarche, acts at higher concentrations to promote bone formation. At the periosteal surface, T promotes bone formation, whereas E2 does not affect it. In addition, OC might be used as a predictor of cortical BMD.
性类固醇在青春期女孩骨骼生长中的作用尚不清楚。骨生物标志物是骨代谢活动的指标，但其在预测生长中女孩骨质量方面的价值尚未得到研究。
本研究探讨青春期女孩性激素和骨标志物与骨几何形态和密度的关联。
本研究设计为对青春期女孩进行的为期2年的纵向研究。在基线以及1年和2年随访时进行测量。
研究在大学实验室进行。
共有258名10至13岁的健康女孩在基线时参与。
使用外周定量计算机断层扫描对左胫骨干进行扫描。评估血清17β-雌二醇（E2）、睾酮（T）、性激素结合球蛋白、骨钙素（OC）、骨特异性碱性磷酸酶和抗酒石酸酸性磷酸酶同工型5b。使用具有随机效应的分层线性模型分析数据。
E2是总骨密度（BMD）、皮质厚度的正向预测因子，是骨内膜周长的负向预测因子，但对总骨横截面积或骨膜周长没有预测价值。T是总横截面积、骨膜周长以及骨内膜周长的正向预测因子，是总BMD的负向预测因子。OC与皮质BMD呈负相关（R2 = 0.325；P < 0.001）。
在青春期女孩中，E2和T对长骨干的骨特性有不同影响。结果表明，在骨内膜表面，E2在快速生长期间抑制骨吸收，初潮后，在较高浓度下起作用促进骨形成。在骨膜表面，T促进骨形成，而E2不影响。此外，OC可能用作皮质BMD的预测指标。
