机械刺激对牙周骨组织工程干细胞分化的影响

Effect of mechanical stimulation on the differentiation of stem cells in periodontal bone tissue engineering

目前,细胞移植及其与支架材料的联合应用仍是牙周骨组织工程的主要策略之一。牙周骨组织中,牙槽骨和牙骨质等组织的硬度及空间结构有明显差异,支架材料的不同机械性能对干细胞的增殖、分化等生物学行为也具有不同诱导作用。研究显示,支架材料的基质硬度和拓扑结构等机械刺激因素参与调控包括脂肪来源间充质干细胞、牙周膜干细胞等在内的种子细胞的多种生物学行为。较硬的基质可促使干细胞的细胞骨架重塑,导致Yes相关蛋白(Yes⁃associated protein,YAP)核易位而影响基因转录,并通过Wnt/β⁃catenin通路释放多种关键因子如碱性磷酸酶、骨钙素等,诱导其向成骨向分化。支架材料的拓扑结构也可影响干细胞的粘着力,促进细胞骨架重构并增加细胞硬度而促进其成骨向分化。笔者就机械刺激对牙周骨组织工程干细胞分化的影响作一综述。

Currently,cell transplantation in combination with scaffold materials are one of the main strategies in periodontal bone tissue engineering.In periodontal bone tissues,the stiffness and spatial structure of tissues such as al⁃veolar bone and cementum differ,and the difference in mechanical properties of scaffolds also has disparate effects on the proliferation and differentiation of stem cells.Accumulating evidence shows that mechanical stimulating factors such as matrix stiffness and scaffold topography modulate biological behaviors of various seeding cells,including adipose⁃de⁃rived stem cells and periodontal ligament stem cells.A hard matrix can promote cytoskeletal stretching of stem cells,leading to nuclear translocation of Yes⁃associated protein(YAP)and promoting osteogenic differentiation by upregulat⁃ing alkaline phosphatase(ALP)and osteocalcin(OCN)via the Wnt/β⁃catenin pathway.The topologic structure of scaf⁃folds can affect cell adhesion and cytoskeletal remodeling,increase the hardness of cells and promote the osteogenic dif⁃ferentiation of stem cells.In this paper,the effects of mechanical stimulation on the differentiation of stem cells in peri⁃odontal bone tissue engineering are reviewed.