丝裂原活化蛋白激酶P38信号途径在人牙髓细胞向成牙本质细胞分化中作用的体外研究

Effects of p38 MAPK signaling pathway on the odontoblastic differentiation of human dental pulp cells

目的:通过观察丝裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)p38抑制剂SB203580在对人牙髓细胞(human dental pulp cells,hDPCs)矿化相关基因的表达和矿化能力的影响,探讨MAPK信号通路在hDPCs向成牙本质细胞分化中的作用。方法:组织块酶消化法体外分离培养hDPCs,并随机分为两组。实验组加入含终浓度为20μmol/L的SB203580矿化液;对照组仅加入矿化液进行诱导培养。于诱导培养7、14、28 d时分别通过RT-PCR、ALP染色和茜素红染色检测各组矿化相关基因的表达水平及其矿化程度。结果:实验组牙本质涎磷蛋白(dentin Sialophosphoprotein,DSPP)、碱性磷酸酶(Alkaline phosphatase,ALP)、骨钙素(Osteonectin,OCN)各矿化相关基因的表达水平,以及hDPCs的碱性磷酸酶活性和矿化结节形成量均低于对照组,差异有统计学意义(P<0.05)。结论:p38MAPK信号通路抑制剂SB203580具有抑制hDPCs分化和矿化的作用,提示p38MAPK信号通路可能参与hDPCs向成牙本质细胞分化。

AIM： To investigate the effects of p38 mitogen-activated protein kinase （MAPK） signaling pathway on the odontoblastic differentiation of human dental pulp cells （hDPCs）. METHODS： Tissue block enzymo-lytic method was used to isolate and culture hDPCs, hDPCs of Passage 3 was cultured with mineralization inducing me-dium containing 20 μmol/L SB203580, a p38 MAPK inhibitor. Cells cultured without SB203580 served as the con-trols. 7 days after induction, quantitative real - time RT - PCR was conducted to detect the mRNA expression of dentin sialophosphoprotein （DSPP） and osteonectin （OCN）. Alkaline phosphatase （ALP） staining and alizarin red S staining were used to examine ALP activity and mineralized nodule formation at 14 d and 28 d after induction, respectively. RESULTS： SB203580 downregulated DSPP, ALP and OCN expression, suppressed ALP activity and mineralized nod- ule formation. CONCLUSION： The p38 MAPK inhibitor SB203580 inhibited the differentiation and mineralization of hDPCs, indicating that p38 MAPK signaling pathway may be involved in hDPCs odontoblastic differentiation.