Hein G, Wiegand R, Lehmann G, Stein G, Franke S
Friedrich-Schiller-University of Jena, Department of Internal Medicine, Germany.
Rheumatology (Oxford). 2003 Oct;42(10):1242-6. doi: 10.1093/rheumatology/keg324. Epub 2003 May 30.
To investigate serum levels of the advanced glycation end-products (AGEs) pentosidine and N epsilon-carboxymethyllysine (CML) in patients classified into different osteoporosis subgroups according to histomorphometric data.
Serum samples were obtained from 116 osteoporotic patients (34 men, 82 women) classified by bone histomorphometry into subgroups with high turnover (HTO, n = 32), low turnover (LTO, n = 39), normal turnover (NTO, n = 9) and cellular uncoupled osteoporosis (CUO, n = 36). Pentosidine was measured by high-performance liquid chromatography, and CML by a competitive enzyme-linked immunoassay.
The entire osteoporosis group had significantly higher pentosidine and CML serum concentrations than healthy subjects. In contrast to healthy subjects, no correlation between levels of AGEs and age could be found. In subgroups characterized by increased bone resorption (HTO, CUO), serum pentosidine correlated significantly with the histomorphometric marker reflecting osteoclast activity/bone resorption (eroded surface as a percentage of trabecular surface). Moreover, in CUO a strong correlation between pentosidine and the mineral apposition rate was found. Surprisingly, in HTO the levels of CML and percentage of eroded surface were significantly negatively correlated.
AGE-modified proteins may be a cause of disturbed bone remodelling in osteoporosis. Our findings do not support the alternative hypothesis that increased AGEs in serum indicate only a more intensive releasing of AGEs in circumstances of increased bone resorption.
根据组织形态计量学数据，研究不同骨质疏松亚组患者血清中晚期糖基化终产物（AGEs）戊糖苷和N-ε-羧甲基赖氨酸（CML）的水平。
从116例骨质疏松患者（34例男性，82例女性）中采集血清样本，这些患者通过骨组织形态计量学分为高转换型（HTO，n = 32）、低转换型（LTO，n = 39）、正常转换型（NTO，n = 9）和细胞解偶联型骨质疏松（CUO，n = 36）亚组。戊糖苷通过高效液相色谱法测定，CML通过竞争性酶联免疫吸附测定法测定。
整个骨质疏松组的血清戊糖苷和CML浓度显著高于健康受试者。与健康受试者不同，未发现AGEs水平与年龄之间存在相关性。在以骨吸收增加为特征的亚组（HTO，CUO）中，血清戊糖苷与反映破骨细胞活性/骨吸收的组织形态计量学标志物（侵蚀表面占小梁表面的百分比）显著相关。此外，在CUO中发现戊糖苷与矿物质沉积率之间存在强相关性。令人惊讶的是，在HTO中，CML水平与侵蚀表面百分比呈显著负相关。
AGE修饰的蛋白质可能是骨质疏松症中骨重塑紊乱的原因。我们的研究结果不支持另一种假设，即血清中AGEs增加仅表明在骨吸收增加的情况下AGEs释放更为强烈。
