Abstract:
Coupling, the mechanism that controls the sequence of events in bone remodelling, is a fundamental theory for understanding the way the skeleton changes throughout life. This review is an adapted version of the Louis V Avioli lecture, delivered at the Annual Scientific Meeting of the American Society of Bone and Mineral Research. It outlines the history of the coupling concept and details how coupling occurs within trabecular and cortical bone and describes its multiple contexts and the many mechanisms suggested to couple bone forming osteoblasts to the prior action of osteoclasts on the same bone surface. These mechanisms include signals produced at each stage of the remodelling sequence (resorption, reversal, and formation), such as factors released by osteoclasts through their resorptive action and through protein synthesis, molecules deposited in the cement line during the reversal phase, and potentially signals from osteocytes within the local bone environment. The review highlights two examples of coupling factors (Cardiotrophin 1 and EphrinB2:EphB4) to illustrate the limited data available, and the need to integrate both the many functions of these factors within the basic multicellular unit (BMU), and the multiple origins of these factors, including other cell types present during the remodelling sequence (such as osteocytes, macrophages, endothelial cells, and T-cells).
Coupling is a fundamental process by which bone resorbing cells (osteoclasts) are followed by bone forming cells (osteoblasts) on the same surface during the process of bone remodelling. This review outlines the history, basic concepts, and mechanisms proposed, and suggests directions for further research into the way this sequence of events in controlled in bone maintenance, development, and healing.
摘要:
联轴器,控制骨骼重塑事件顺序的机制,是理解骨骼在整个生命中变化方式的基本理论。这篇评论是LouisVAvoli演讲的改编版,在美国骨与矿物研究学会年度科学会议上发表。它概述了耦合概念的历史,并详细介绍了如何在小梁和皮质骨内发生耦合,并描述了其多种背景以及将形成骨的成骨细胞与破骨细胞在同一骨表面上的先前作用耦合的许多机制。这些机制包括在重塑序列的每个阶段产生的信号(再吸收,反转,和形成),如破骨细胞通过其吸收作用和蛋白质合成释放的因子,在反转阶段沉积在水泥线中的分子,以及来自局部骨骼环境中骨细胞的潜在信号。该综述强调了两个耦合因子的例子(心肌营养素1和EphrinB2:EphB4),以说明可用的有限数据,并且需要将这些因素的许多功能整合到基本多细胞单位(BMU)中,这些因素的多重起源,包括在重塑序列期间存在的其他细胞类型(例如骨细胞,巨噬细胞,内皮细胞,和T细胞)。
偶联是在骨重塑过程中骨再吸收细胞(破骨细胞)跟随在同一表面上的骨形成细胞(成骨细胞)的基本过程。这篇评论概述了历史,基本概念,和提出的机制,并为进一步研究这一系列事件在骨骼维持中的控制方式提供了方向,发展,和愈合。