Abstract: Objective: To evaluate  the proliferation and osteogenic differentiation potentials of bone mesenchymal stem cells (BMSCs) derived from the alveolar bone where tooth extraction was performed at different time points previously. Methods: Eight-weeks old  male SD rats were used, and their maxillary molars on the right side were extracted to create the model. The animals were sacrificed at 1-, 4-, and, 12- week respectively after tooth extraction. BMSCs were isolated from alveolar bone and cultured in vitro. The proliferation potential was measured by cck-8, osteogenic differentiation of BMSCs were determined by measuring calcium accumulation using alizarin red-sulfate(AR-S) staining, and semi-quantitative PCR analysis of osteogenic markers (ALP, Runx2 and OCN). Results: BMSCs derived from alveolar bone at different time points after extraction manifested no difference on capacity of proliferation. But calcium accumulation and mRNA levels of alkaline phosphatase (ALP), runt-related transcription factor 2 (Runx2) and osteocalcin (OCN) were demonstrated overexpression in BMSCs which derived from the alveolar bone 4 weeks after extraction, while those were low expression in the 12 weeks after extraction. Conclusion: Our findings demonstrate that there is no difference in the proliferation potential of BMSCs, isolated from alveolar bone where extraction of tooth were performed at any different time points. befor harvest.e. But osteogenic differentiation potential is significantly different.

Key words: extraction, alveolar bone, bone marrow mesenchymal stem cells (BMSCs), proliferation, osteogenic differentiation

摘要： 目的：通过分离培养大鼠拔牙后不同时间点牙槽骨组织来源的骨髓间充质干细胞（BMSCs），探讨拔牙后不同时间点BMSCs的增殖及成骨分化能力。方法：选用8周龄健康雄性SD大鼠，拔除上颌右侧磨牙建立动物模型，分别于拔牙后1、4及12周处死大鼠。取拔牙后各时间点牙槽骨组织BMSCs进行培养及鉴定，通过cck-8检测各组BMSCs增殖情况，对比各组成骨诱导后茜素红染色及q-PCR检测钙结节形成及成骨相关基因的表达，比较各组BMSCs的增殖及成骨分化能力。结果：拔牙后各时间点获得的牙槽骨组织BMSCs增殖能力无差异；经成骨诱导后茜素红染色显示，拔牙后4周形成的钙结节最多，12周最少；成骨诱导后q-PCR检测ALP、Runx2、OCN的表达，结果3种基因均在拔牙后4周时表达最高，12周时最低，且差异具有统计学意义。结论：拔牙后不同时间点牙槽骨组织BMSCs的增殖能力没有明显差异，但4周时来源的BMSCs成骨能力最强，与其他时间组有差异。

关键词: 拔牙, 牙槽骨, 骨髓间充质干细胞, 增殖, 成骨分化能力

CLC Number: 

• R782.1