miR-135b和miR-335在不同年龄人牙髓细胞成牙本质向分化中的差异表达

Differential expression of miR-135b and miR-335 in age-related human dental pulp cells during odontogenic differentiation

目的探讨不同年龄阶段人牙髓细胞(HDPCs)在矿化诱导前后miR-135b和miR-335的表达变化,及其在HDPCs分化中的作用。方法提取青年(18～22岁)及中年(46～48岁)临床就诊患者第三磨牙的HDPCs,经体外培养至第3代后,用矿化诱导液诱导细胞向成牙本质细胞方向分化,对细胞结节形成情况进行观察并用VonKossa染色、碱性磷酸酶检测确定HDPCs分化情况,分别取培养0、7、14、21和28d的细胞用定量反转录聚合酶链反应(qRT-PCR)检测miR-135b和miR-335的表达变化。结果青年组HDPCs中miR-135b和miR-335显著高于中年组(P<0.05);经矿化诱导后,青年组miR-135b和miR-335表达逐渐降低(P<0.05),而中年组miR-135b表达上升,miR-335表达则维持在低水平。结论 miR-135b和miR-335在不同年龄阶段HDPCs中差异表达,可能在HDPCs成牙本质向分化中具有重要作用。

Objective To identify the expression of miR-135b and miR-335 of age-related in ages human dental pulp cells （HDPCs） during odontogenic differentiation. Methods Human dental pulp cells from youth adults （18-22 years） and middle-aged adults （46-48 years） were isolated,cultured and identified in vitro, the expression of miR-135b and miR-335 in HDPCs were examined during odontogenic differentiation by qRT-PCR. The formation of cellular nodules were determined. The cell differentiation was evaluated by Von Kossa staining and activity of alkaline phosphatase. Results The expression of miR-135b and miR-335 in youth HDPCs was significantly higher than that of middl- caged group （P 〈 0.05）. The miR-135b and miR-335 expression in youth HDPCs gradually decreased with the cell passage and odontoblasts directional differentiation （P 〈 0.05）. In contrast, the expression of miRNA-135b was significantly increased in cell with differentiation in middle-aged HDPCs （P 〈 0.05）. Conclusion The expression of miR-135b and miR-335 might play important roles in age-related human dental pulp cells during directional differentiation into odontoblastic cell.