Osteoclasts generate cross-linked collagen N-telopeptides (NTx) but not free pyridinolines when cultured on human bone
Osteoclasts generate cross-linked collagen N-telopeptides (NTx) but not free pyridinolines when cultured on human bone
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DOI：
10.1016/s8756-3282(97)00105-1
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发表时间：
1997-08-01
期刊：
影响因子：
4.1
通讯作者：
Eyre, DR
中科院分区：
文献类型：
--
作者：
Apone, S;Lee, MY;Eyre, DR
I型胶原的交联α 2（I）N-端肽（NTx）的尿排泄在临床研究中已被证明提供了骨吸收的高度响应性和特异性指标。为了更好地理解该标记物的特异性和响应性的生物学基础，我们检测了在人骨上培养的破骨细胞是否能产生免疫反应性NTx肽，小鼠骨髓培养物用1，25二羟维生素D-3（1，25（OH）（2）D-3）和氢化可的松产生破骨细胞，在人骨颗粒或牙本质切片上共培养，用酶联免疫吸附试验（ELISA）测定等份培养基中的NTx，添加骨5天后培养基中检测到NTx，并在14天的培养期内继续线性产生，NTx的生产需要附着在骨颗粒或牙本质切片的单核和多核细胞，染色抗酒石酸酸性磷酸酶。吸收牙本质的表面积与NTx浓度呈高度相关（R-2 = 0.84），破骨细胞抑制剂降钙素和阿仑膦酸钠以剂量依赖方式抑制NTx的产生。另外两种骨吸收标志物羟赖氨酰吡啶啉和赖氨酰吡啶啉在培养液中以肽键形式存在，而非游离形式;表明破骨细胞已将骨胶原降解为肽，但未降解为游离的交联氨基酸。(C)Elsevier Science Inc.出版。All rights reserved.
Urinary excretion of the cross-linked alpha 2(I) N-telopeptide (NTx) of type I collagen has proven in clinical studies to provide a highly responsive and specific index of bone resorption, In order to understand better the biological basis of the specificity and responsiveness of this marker, we examined whether osteoclasts cultured on human bone could generate immunoreactive NTx peptide, Mouse bone marrow cultures stimulated with 1,25 dihydroxyvitamin D-3 (1,25(OH)(2)D-3) and hydrocortisone to produce osteoclasts, were cocultured on human bone particles or dentin slices, Aliquots of culture medium were assayed for NTx by enzyme-linked immunosorbent assay (ELISA), NTx was detected in the medium 5 days after the addition of bone and continued to be produced linearly over the 14-day culture period, NTx production required attachment to the bone particles or dentin slices of mononuclear and multinuclear cells that stained for tartrate-resistant acid phosphatase. Surface area of resorbed dentin was highly correlated with medium NTx concentration (R-2 = 0.84), Production of NTx was suppressed by the osteoclast inhibitors, calcitonin and alendronate, in a dose-dependent manner, Two other markers of bone resorption, hydroxylysyl pyridinoline and lysyl pyridinoline, were found in peptide linkage in the culture medium but not in free form; indicating that the osteoclasts had degraded the bone collagen to peptides but not to the free cross-linking amino acids. (C) 1997 by Elsevier Science Inc. All rights reserved.