Abstract:

Objective: To compare the effects of estrogen (EST) and platelet-rich fibrin (PRF) on the expression of Runx2, microRNA-17 (miR-17) and bone morphogenetic protein2 (BMP2) in bone marrow derived mesenchymal stem cells (BMSCs) of human alveolar bone. Methods: The bone fragments in alveolar bone fossa were collected during clinical tooth extraction. BMSCs were isolated and cultured in vitro by enzyme digestion, the morphology of cell growth was observed under microscope. The experiment was divided into three groups: estrogen treatment group (EST group, concentration 10^-8 mol/L), platelet-rich fibrin treatment group (PRF group) and control group(DMEM complete medium). After culture, the proliferation rate of BMSCs was detected by MTT assay, the activity of alkaline phosphatase was detected by enzyme labeling instrument, the expression level of Runx2, miR-17 was detected by qRT-PCR and the expression level of BMP2 was detected by western blot assay. Results: The numbers of cells and alkaline phosphatase activities in the three groups reached the highest level on the 7th day, and then the proliferation rate decreased gradually. The cell proliferation rate in PRF group and EST group was significantly higher than that in the control group at the beginning of the 3rd day (P<0.05). After 7 days of culture, the expression level of BMP2 and Runx2 protein in PRF group and EST group was significantly higher than that in the control group (P<0.05). After 7 days of culture, the level of miR-17 in BMSCs decreased significantly, while the level of Runx2 increased significantly. The expression level of miR-17 and Runx2 in the PRF group and EST group was significantly better than that in the control group on the 7th day (P<0.05). Conclusion: Estrogen and platelet-rich fibrin can effectively promote the expression of Runx2, miR-17 and BMP2 in BMSCs of human alveolar bone, which is beneficial to the proliferation and differentiation of BMSCs.

Key words: estrogen, platelet-rich fibrin, bone marrow mesenchymal stem cells, Runx2, miR-17, bone morphogenetic protein 2

摘要：

目的：比较雌激素（estrogen, EST）和富血小板纤维蛋白（platelet-rich fibrin, PRF）对人牙槽骨骨髓间充质干细胞（bone marrow mesenchymal stem cells, BMSCs）中Runt 家族相关转录因子2（runt-related transcription factor2，Runx2）、微小RNA17（microRNA，miR-17）及骨形态发生蛋白2（bone morphogenetic protein 2, BMP2）表达的影响。方法：在临床拔牙过程中收集牙槽窝内的骨屑，经酶消化法体外分离培养得BMSCs，并于显微镜下观察细胞的生长形态。实验分为3组，雌激素（estrogen, EST）处理组（EST组，浓度10^-8 mol/L）、富血小板纤维蛋白治疗组（PRF组）及对照组（DMEM完全培养基组）。3组细胞经培养后采用MTT法检测细胞增殖率，采用酶标仪检测碱性磷酸酶活性， RT-qPCR检测Runx2、miR-17表达水平，Western blot法检测BMP2表达水平。结果：3组细胞培养7 d后细胞数量、碱性磷酸酶活性达到最高水平，随后增殖速率逐渐减慢，其中PRF组、EST组细胞于第3天开始细胞增殖速率均显著高于对照组（P<0.05）。培养7 d后，PRF组、EST组BMP-2及Runx2蛋白表达水平显著高于对照组（P<0.05）。BMSCs培养7 d后miR-17水平显著降低，而Runx2水平显著增加，其中PRF组、EST组在培养7 d时表达水平显著优于对照组（P<0.05）。结论：雌激素、富血小板纤维蛋白均可有效促进人牙槽骨BMSCs中Runx2、miR-17及BMP2的表达，从而有利于BMSCs的增殖、分化。

关键词: 雌激素, 富血小板纤维蛋白, 骨髓间充质干细胞, Runt 家族相关转录因子2, 微小RNA17, 骨形态发生蛋白2