The reversal phase of the bone-remodeling cycle: cellular prerequisites for coupling resorption and formation.
The reversal phase of the bone-remodeling cycle: cellular prerequisites for coupling resorption and formation.
复制标题
骨重塑周期的逆转阶段：将吸收和形成结合起来的细胞先决条件。
DOI：
10.1038/bonekey.2014.56
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
Delaisse, Jean-Marie
中科院分区：
文献类型：
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作者：
Delaisse, Jean-Marie
逆转阶段通过在重塑部位产生成骨环境将骨吸收与骨形成耦合。尽管已经发现了一些“偶联”成骨分子，但偶联机制仍然知之甚少。一个可能的原因是在逆转阶段对导致成骨的细胞缺乏关注。这篇综述的目的是创造这些细胞和他们的活动在成人松质骨的认识。它涉及细胞事件(i)在骨表面，（ii）在骨髓周围的间充质包膜中，并在重塑表面上以冠层的形式出现，以及（iii）在距离该冠层50 μm范围内的骨髓本身。当骨重塑开始时，这三种不同水平的骨祖细胞被激活，可能是细胞-细胞和细胞-基质相互作用重排的结果。值得注意的是，冠层受到毛细血管和破骨细胞的成骨影响，而骨表面细胞则暴露于侵蚀基质和其他破骨细胞产物。在几种不同的病理生理情况下，包括骨质疏松症，来自这些局部储存库的成骨祖细胞的可用性减少与成骨细胞募集减少和骨形成开始受损相一致，即解偶联。总之，这篇综述强调，偶联不仅依赖于能够激活成骨的分子，而且还需要骨祖细胞的存在和重塑部位的有序细胞重排。它指出保护局部骨祖细胞是防止骨质流失的关键策略。
The reversal phase couples bone resorption to bone formation by generating an osteogenic environment at remodeling sites. The coupling mechanism remains poorly understood, despite the identification of a number of ‘coupling' osteogenic molecules. A possible reason is the poor attention for the cells leading to osteogenesis during the reversal phase. This review aims at creating awareness of these cells and their activities in adult cancellous bone. It relates cell events (i) on the bone surface, (ii) in the mesenchymal envelope surrounding the bone marrow and appearing as a canopy above remodeling surfaces and (iii) in the bone marrow itself within a 50-μm distance of this canopy. When bone remodeling is initiated, osteoprogenitors at these three different levels are activated, likely as a result of a rearrangement of cell–cell and cell–matrix interactions. Notably, canopies are brought under the osteogenic influence of capillaries and osteoclasts, whereas bone surface cells become exposed to the eroded matrix and other osteoclast products. In several diverse pathophysiological situations, including osteoporosis, a decreased availability of osteoprogenitors from these local reservoirs coincides with decreased osteoblast recruitment and impaired initiation of bone formation, that is, uncoupling. Overall, this review stresses that coupling does not only depend on molecules able to activate osteogenesis, but that it also demands the presence of osteoprogenitors and ordered cell rearrangements at the remodeling site. It points to protection of local osteoprogenitors as a critical strategy to prevent bone loss.