Molecular regulation system of cytodifferentiation due to mechanical stress

采用免疫组化方法检测机械应力作用下小鼠牙周韧带中Runx2和Msx2的早期表达变化。Runx2、BMP、HSP的表达随时间呈平行增强趋势，牙周成纤维细胞、成水泥细胞、成骨细胞表达较强。此外，ALP也表现出类似的强表达。这些结果强烈提示Runx2促进成骨细胞早期分化，而Msx2是Runx2功能的激活剂。此外，这也表明这些热热蛋白在成骨细胞的激活和维持中起着分子伴侣的作用。

Early changes of Runx2 and Msx2 expressions were examined by immunohistochemistry in mouse periodontal ligament exposed to mechanical stress. Expressions of Runx2, BMP and HSP became stronger in parallel with time, the periodontal fibroblasts, cementoblasts as well as osteoblasts showed strong expression. Moreover, ALP has also demonstrated similar strong expression. All these results strongly suggested that Runx2 promoted differentiation of osteoblasts at early stage and Msx2 worked as an activator of Runx2 function. Furthermore, it also suggests that these HSP act as molecular chaperones for osteoblast activation and maintenance.