胞外信号调节激酶1/2信号转导通路调控牙周膜细胞成骨分化的研究

Extracellular signal-regulated kinase 1/2 signal pathway regulates the osteogenic differentiation of periodontal ligament cells

目的探索细胞外信号调节激酶(ERK 1/2信号转导通路是否参与调控牙周膜细胞的成骨分化。方法取体外培养的第3代牙周膜细胞进行研究。实验分为空白对照组、成骨诱导组和实验组(在成骨诱导培养基中加入10 nmol·L-1 ERK1/2磷酸化的抑制剂PD98059)。培养1周和3周后通过定量聚合酶链反应(q PCR)、碱性磷酸酶(ALP)染色和茜素红染色检测其成骨能力。结果成骨诱导可促进牙周膜细胞中ERK1/2的磷酸化。培养1周后,抑制ERK1/2的磷酸化可上调成骨标志物Runx2、ALP和骨钙蛋白(OCN)的表达,与成骨诱导组相比较,OCN的表达差异具有统计学意义(P<0.05),Runx2、ALP的表达差异也具有统计学意义(P<0.01)。培养3周后,实验组牙周膜细胞成骨标志物Runx2、ALP和OCN的表达仍较成骨诱导组高,ALP染色和钙结节形成较成骨诱导组强,其中Runx2、ALP的表达差异具有统计学意义(P<0.05),OCN的表达差异也具有统计学意义(P<0.01)。结论 ERK1/2信号转导通路参与了调控体外培养的牙周膜细胞的成骨分化。

Objective This study aims to explore whether the extracellular signal-regulated kinase（ERK） 1/2 signaling pathway could regulate the osteogenic differentiation of periodontal ligament cells. Methods The human periodontal ligament cells from the third passage were divided into three groups, namely, black control group, osteogenic induction group, and experimental group（10 nmol·L-1 PD98059, an inhibitor of ERK1/2 phosphorylation, was added in the osteogenic medium）. One or three weeks after culture, the osteogenic capability of the periodontal ligament cells was evaluated using quantitative polymerase chain reaction（q PCR）, alkaline phosphatase（ALP） staining, and alizarin red staining. Results Osteogenic induction promoted ERK1/2 phosphorylation. One week after culture, inhibition of ERK1/2 phosphorylation up regulated the expression of Runx2, ALP, and osteocalcin（OCN） in periodontal ligament cells. Statistically significant differences were found in OCN and the osteogenic induction group（P〈0.05）, and statistically significant differences were found in ALP and Runx2（P〈0.01）. Three weeks after culture, the expression of Runx2, ALP, and OCN remained higher in the experimental group than in the osteogenic induction group. In addition, strong ALP staining and more calcium nodule formation were observed in the periodontal ligament cells of the experimental group. Statistically significant differences were found in ALP and Runx2（P〈0.05）, and statistically differences were found in OCN（P〈0.01）. Conclusion The ERK1/2 signal pathway could regulate the osteogenic differentiation of periodontal ligament cells in vitro.