Abstract: Objective　To study the effects of histone demethylase Jmjd3 on odontogenic differentiation of dental pulp stem cells（DPSCs）. Methods　The primary DPSCs were isolated from human dental pulp tissue，and identified by flow cytometry and Alizarin red staining. DPSCs were cultured in odontogenic induction medium for 0，3，5，7 and 14 days，and the expressions of Jmjd3，DSPP and DMP1 were determined by qRT-PCR. DPSCs were treated with different concentrations of GSK-J4（0，1，10 μmol/L） for 14 days，which was the specific inhibitor of Jmjd3，and the gene expressions of DSPP and DMP1 were determined by qRT-PCR. Results　The primary DPSCs expressed mesenchymal stem cell surface markers CD44，CD29 and CD146，and had the capacity of osteogenic differentiation. The gene expressions of Jmjd3，DSPP and DMP1 were up-regulated during the process of odontogenic differentiation（P < 0.05），which might be time-dependent. The expressions of DSPP and DMP1 were inhibited significantly after treatment with 10 μmol/L GSK-J4（P < 0.05）. Conclusion　Histone demethylase Jmjd3 plays a positive role in regulating odontogenic differentiation of DPSCs，and it may be related to the demethylase activity of Jmjd3.

Key words: dental pulp stem cells, DPSCs；histone demethylase Jmjd3；odontogenic differentiation；GSK-J4

摘要： 目的　研究组蛋白去甲基化酶Jmjd3对牙髓干细胞（dental pulp stem cells，DPSCs）成牙本质向分化的影响。方法　原代分离培养DPSCs，用流式细胞术和茜素红染色鉴定DPSCs。体外诱导DPSCs成牙本质向分化不同时间（0、3、5、7、14 d），qRT-PCR检测Jmjd3及成牙本质细胞标志物牙本质涎磷蛋白（dentin sialophosphoprotein，DSPP）、牙本质基质蛋白1（dentin matrix protein1，DMP1）的表达情况。用不同浓度（0、1、10 μmol/L）的Jmjd3抑制剂GSK-J4处理DPSCs 14 d，qRT-PCR检测DSPP、DMP1的表达情况。结果　原代培养的DPSCs表达间充质干细胞表面标记物CD44、CD29、CD146，体外诱导培养具有成骨分化潜能。DPSCs成牙本质向分化过程中，Jmjd3、DSPP、DMP1表达水平均上调（P < 0.05），且可能具有时间依赖性。10 μmol/L GSK-J4处理DPSCs可明显抑制DSPP、DMP1的表达（P < 0.05）。结论　Jmjd3在DPSCs成牙本质向分化过程中发挥正调节作用，且与其去甲基化酶活性相关。

关键词: 牙髓干细胞, 组蛋白去甲基化酶Jmjd3, 成牙本质向分化, GSK-J4