Mora S, Prinster C, Proverbio M C, Bellini A, de Poli S C, Weber G, Abbiati G, Chiumello G
Laboratory of Pediatric Endocrinology and Department of Pediatrics, Scientific Institute H San Raffaele, University of Milan, via Olgettina 60, 20132 Milan MI, Italy.
Calcif Tissue Int. 1998 Nov;63(5):369-74. doi: 10.1007/s002239900542.
During growth, bones change their dimensions rapidly with the changes involving both formation and resorption processes. Small cross-linked peptides coming from type I collagen molecules are excreted in urine when bone is resorbed. To date, conflicting results have been presented concerning the age- and puberty-related changes of urinary markers. The purpose of the present study was to verify the effect of age, gender, and puberty on the urinary excretion of type I collagen degradation products in healthy children and adolescents. Timed spot urines from 176 children (4-20 years old) and 50 young adults were analyzed. The concentrations of N-telopeptides of type I collagen (NTx), pyridinolines (Pyr), and deoxypyridinolines (Dpyr) were measured, and the results were normalized to creatinine. Age-related changes in cross-links excretion were observed. The levels decreased with age, and a peak of excretion was shown at the beginning of adolescence. Prepubertal levels of all the markers were four- to five-fold higher than in adults, and they decreased towards adult levels in late puberty. Girls had significantly higher levels of all biochemical markers than boys at pubertal stage 2. We also observed a remarkable effect of puberty on the levels of bone degradation products that was independent of age and gender. Our results indicate that bone resorption is high in children relative to that in adults, and that urinary levels of NTx, Pyr, and Dpyr change as a function of age, gender, and puberty.
在生长过程中，骨骼会随着涉及形成和吸收过程的变化而迅速改变其尺寸。当骨骼被吸收时，来自I型胶原分子的小交联肽会随尿液排出。迄今为止，关于尿标志物与年龄和青春期相关变化的研究结果相互矛盾。本研究的目的是验证年龄、性别和青春期对健康儿童和青少年尿液中I型胶原降解产物排泄的影响。对176名儿童（4至20岁）和50名年轻人的定时尿样进行了分析。测量了I型胶原N-端肽（NTx）、吡啶啉（Pyr）和脱氧吡啶啉（Dpyr）的浓度，并将结果以肌酐进行标准化。观察到交联物排泄与年龄相关的变化。这些水平随年龄下降，在青春期开始时出现排泄高峰。所有标志物的青春期前水平比成年人高四至五倍，在青春期后期降至成人水平。在青春期2期，女孩的所有生化标志物水平均显著高于男孩。我们还观察到青春期对骨降解产物水平有显著影响，且这种影响独立于年龄和性别。我们的结果表明，儿童的骨吸收相对于成年人较高，并且尿液中NTx、Pyr和Dpyr的水平会随着年龄、性别和青春期而变化。
