周期性机械牵拉通过上调Runx2表达促进MC3T3-E1细胞迁移

目的 探究周期性牵拉对小鼠胚胎成骨细胞MC3T3-E1迁移功能的影响及其相关机制。方法 使用应变加载系统对体外培养的MC3T3-E1细胞施加15%幅度的牵拉，模拟细胞体内受力情况。使用划痕愈合实验检测MC3T3-E1细胞的迁移功能，使用蛋白免疫印迹法检测Runx2表达情况，使用RNA干扰技术特异性降低Runx2表达量。结果 幅度15%、频率1.25 Hz、持续24 h的周期性机械牵拉可以促进MC3T3-E1细胞的迁移，升高细胞内Runx2表达水平。在静态培养条件下，干扰Runx2能抑制MC3T3-E1细胞的迁移。干扰MC3T3-E1细胞中Runx2表达可以部分降低机械牵拉对细胞迁移的促进效应。结论 周期性牵拉可以促进MC3T3-E1细胞的迁移，在此过程中Runx2可能发挥重要作用。研究结果为寻找促进骨折愈合的创新临床治疗方法提供实验依据。

Cyclic Stretch Promotes Migration of MC3T3-E1 Cells via Increasing Runx2 Expression

Objective To investigate the effects of cyclic stretch on migration of MC3T3-E1 cells and its related mechanism. Methods The strain loading system was used to stretch MC3T3-E1 cells cultured in vitro with 15% amplitude, to simulate the mechanical condition in vivo. The wound healing assay was used to detect the migration of MC3T3-E1 cells. Western blotting was used to test Runx2 expression. RNA interfering was used to decrease Runx2 expression. Results Cyclic mechanical stretch with 15% amplitude, 1.25 Hz frequency and lasting for 24 hours could promote the migration of MC3T3-E1 cells and increase the expression level of Runx2. Runx2 interference inhibited the migration of MC3T3-E1 cells in static culture condition. Interference with Runx2 expression in MC3T3-E1 cells could partially reduce the positive effect of cyclic mechanical stretch on cell migration. Conclusions Cyclic stretch can promote the migration of MC3T3-E1 cells, and Runx2 may play an important role in this process. This study provides experimental basis for finding innovative clinical treatment method to promote fracture healing.