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

摘要

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20 μmol/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) signalingrnpathway 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 medium containing 20 μmol/L SB203580, a p38 MAPK inhibitor. Cells cultured without SB203580 served as the controls. 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 nodule 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.