Notch和Wnt信号通路在自体骨髓间充质干细胞复合富血小板纤维蛋白修复兔牙槽骨缺损中的表达

目的通过建立自体骨髓间充质干细胞（BMSCs）复合富血小板纤维蛋白（PRF）修复兔拔牙窝骨缺损的动物模型，探讨Notch和Wnt信号通路在牙槽骨缺损修复过程中的表达及意义。方法 选用36只健康雄性2月龄新西兰兔，随机分为4组，均于全身麻醉下微创拔除下颌左侧中切牙。A组植入BMSCs-PRF复合物，B、C组分别植入单一PRF和BMSCs，D组未植入任何材料作为空白对照。术后4、8、12周（每个时间点3只动物）处死动物，立即在骨缺损同一部位取材，制作骨标本，利用免疫组织化学和免疫荧光染色检测骨缺损修复过程中Notch1和Wnt3a的表达情况。结果 免疫组织化学染色结果显示：第4、8周，A、B、C组Notch1和Wnt3a表达均高于D组（P<0.05）；第12周，D组Notch1和Wnt3a表达高于其他3组（P<0.05）。免疫荧光染色显示：第4周，骨缺损区新生骨细胞Notch1和Wnt3a的表达最多，随着时间的延长，骨缺损修复完成，表达逐渐降低。结论 Notch1和Wnt3a信号分子在BMSCs复合PRF促进骨缺损修复过程中均有表达，可以通过调控BMSCs的增殖与分化加速牙槽骨缺损修复的愈合过程；二者表达情况相似，有可能存在串话机制。

The expressions of the Notch and Wnt signaling pathways and their significance in the repair process of alveolar bone defects in rabbits with bone marrow stem cells compounded with platelet-rich fibrin

ObjectiveWe explored the expressions of the Notch and Wnt signaling pathways and their significance in the repair process of alveolar bone defects by establishing animal models with a composite of autologous bone marrow mesenchymal stem cells (BMSCs) and platelet-rich fibrin (PRF) to repair bone defects in the extraction sockets of rabbits. MethodsA total of 36 two-month-old male New Zealand white rabbits were randomly divided into four groups, and the left mandibular incisors of all the rabbits were subjected to minimally invasive removalunder general anesthesia. BMSC-PRF compounds, single PRF, and single BMSC were implanted in Groups A, B, and C. No material was implanted in Group D (blank control). The animals were sacrificed at 4, 8 and 12 weeks after surgery, the bone defect was immediately drawn, and the bone specimens underwent surgery after four, eight, and twelve weeks, with three rabbits per time point. The expressions of Notch1 and Wnt3a in the repair process of the bone defect were measured via immunohistochemical and immunofluorescence detection. Results Immunohistochemistry showed that the expressions of Notch1 and Wnt3a in Groups A, B, and C were higher than that in Group D at the fourth and eighth week after operation (P<0.05). By contrast, the expressions of Notch1 and Wnt3a in Group D were higher than those in Groups A, B, and C at the twelfth week (P<0.05). Immunofluorescence showed that the expressions of both Notch1 and Wnt3a reached their peaks in the new bone cells of the bone defect after four weeks following surgery and gradually disappeared when the bone was repaired completely. ConclusionNotch1 and Wnt3a signaling molecules are expressed in the process of repairing bone defects using BMSC-PRF composites and can accelerate the healing by regulating the proliferation and differentiation of BMSCs. Moreover, the expressions of Notch and Wnt are similar, and a crosstalk between them may exist.