Role of Periostin in Adhesion and Migration of Bone Remodeling Cells

Periostin is an extracellular matrix protein highly expressed in collagen-rich tissues subjected to continuous mechanical stress. Functionally, periostin is involved in tissue remodeling and its altered function is associated to numerous pathological processes. In orthodontics, periostin plays key roles in the maintenance of dental tissues and it is mainly expressed in those areas where tension or pressing forces are taking place. In this regard, high expression of periostin is essential to promote migration and proliferation of periodontal ligament fibroblasts. However little is known about the participation of periostin in migration and adhesion processes of bone remodeling cells. In this work we employ the mouse pre-osteoblastic MC3T3-E1 and the macrophage-like RAW 264.7 cell lines to overexpress periostin and perform different cell-based assays to study changes in cell behavior. Our data indicate that periostin overexpression not only increases adhesion capacity of MC3T3-E1 cells to different matrix proteins but also hampers their migratory capacity. Changes on RNA expression profile of MC3T3-E1 cells upon periostin overexpression have been also analyzed, highlighting the alteration of genes implicated in processes such as cell migration, adhesion or bone metabolism but not in bone differentiation. Overall, our work provides new evidence on the impact of periostin in osteoblasts physiology.

骨膜蛋白（Periostin）是一种在持续承受机械应力的富含胶原的组织中高表达的细胞外基质蛋白。功能上，骨膜蛋白参与组织重塑过程，其功能异常与多种病理进程密切相关。在正畸学领域，骨膜蛋白在维持牙组织稳态中发挥关键作用，主要表达于存在牵张力或压力的区域。在此背景下，骨膜蛋白的高表达对于促进牙周膜成纤维细胞的迁移与增殖至关重要。然而，目前对于骨膜蛋白在骨重塑细胞的迁移及黏附过程中的参与机制仍知之甚少。本研究选用小鼠前成骨细胞MC3T3-E1与巨噬细胞样RAW 264.7细胞系，通过过表达骨膜蛋白并开展多种基于细胞的实验以探究细胞行为变化。研究结果显示，骨膜蛋白过表达不仅可提升MC3T3-E1细胞对不同基质蛋白的黏附能力，还会抑制其迁移能力。本研究同时分析了骨膜蛋白过表达后MC3T3-E1细胞的RNA表达谱变化，发现与细胞迁移、黏附或骨代谢相关的基因表达发生改变，但骨分化相关基因未出现显著异常。综上，本研究为骨膜蛋白对成骨细胞生理功能的影响提供了新的实验依据。