Department of Biomedical Engineering, Indiana University-Purdue University at Indianapolis, Indianapolis, IN, United States.
Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, United States.
Front Endocrinol (Lausanne). 2021 Jan 18;11:578477. doi: 10.3389/fendo.2020.578477. eCollection 2020.
Osteocytes make up 90-95% of the cellular content of bone and form a rich dendritic network with a vastly greater surface area than either osteoblasts or osteoclasts. Osteocytes are well positioned to play a role in bone homeostasis by interacting directly with the matrix; however, the ability for these cells to modify bone matrix remains incompletely understood. With techniques for examining the nano- and microstructure of bone matrix components including hydroxyapatite and type I collagen becoming more widespread, there is great potential to uncover novel roles for the osteocyte in maintaining bone quality. In this review, we begin with an overview of osteocyte biology and the lacunar-canalicular system. Next, we describe recent findings from models of osteocytes, focusing on the transitions in cellular phenotype as they mature. Finally, we describe historical and current research on matrix alteration by osteocytes , focusing on the exciting potential for osteocytes to directly form, degrade, and modify the mineral and collagen in their surrounding matrix.
成骨细胞构成了骨骼细胞内容物的 90-95%，并形成了一个丰富的树突状网络，其表面积比成骨细胞或破骨细胞都要大得多。成骨细胞通过直接与基质相互作用，很好地处于在骨稳态中发挥作用的位置；然而，这些细胞修饰骨基质的能力仍然不完全清楚。随着用于检查骨基质成分（包括羟磷灰石和 I 型胶原蛋白）的纳米和微观结构的技术变得更加普及，人们有很大的潜力揭示成骨细胞在维持骨质量方面的新作用。在这篇综述中，我们首先概述了成骨细胞生物学和骨陷窝-小管系统。接下来，我们描述了成骨细胞模型的最新发现，重点介绍了细胞表型的转变，因为它们成熟。最后，我们描述了成骨细胞对基质改变的历史和当前研究，重点介绍了成骨细胞直接形成、降解和修饰其周围基质中的矿物质和胶原蛋白的令人兴奋的潜力。
