P2X7受体在人牙周膜干细胞成骨分化中的作用

目的：探讨P2X7受体（P2X7 receptor,P2X7r）在人牙周膜干细胞成骨分化中的作用。方法：选取就诊于贵州中医药大学第一附属医院的健康青年患者因正畸需要而拔除的前磨牙为实验材料,分离、培养人牙周膜干细胞（human periodontal ligament stem cells,hPDLSCs）。取第4代hPDLSCs,分为A、B、C、D 4组,A组用常规培养液培养,B组用成骨诱导液培养,C组用成骨诱导液+100 nmol/L三磷酸腺苷（adenosine triphosphate,ATP）溶液培养,D组用成骨诱导液+100 nmol/L P2X7受体特异性拮抗剂KN-62培养。7 d后,采用茜素红染色观察各组hPDLSCs成骨效果,采用实时荧光定量反转录PCR（RT-PCR）检测各组hPDLSCs成骨相关因子骨钙素（osteocalcin,OCN）、RUNX2 mRNA的表达量,采用RT-PCR检测各组hPDLSCs中P2X7r mRNA表达。采用SPSS 22.0软件包对结果进行统计学分析。结果：茜素红染色结果显示,B组和C组hPDLSCs细胞形态发生显著变化,逐渐由不规则形变为方形,出现灰白色钙化小结节。结节多呈板层状圆形或椭圆形团块,C组灰白色钙化小结节显著多于B组,而A组和D组钙结节量均很少。B、C组hPDLSCs中OCN、RUNX2、P2X7r mRNA表达量显著高于A组（P<0.05）,C组hPDLSCs中OCN、RUNX2、P2X7r mRNA表达量显著高于B组（P<0.05）,D组hPDLSCs中OCN、RUNX2、P2X7r mRNA表达量显著低于B、C组（P<0.05）,D组hPDLSCs中OCN、RUNX2、P2X7r mRNA表达量与A组相比,差异无统计学意义（P>0.05）。结论： P2X7受体在人牙周膜干细胞成骨分化中发挥正调节作用。P2X7受体被ATP激活后,可促进人牙周膜干细胞成骨分化,这为临床上治疗牙周炎提供了新的方向。

Role of P2X7 receptor in osteogenic differentiation of human periodontal ligament stem cells

PURPOSE: To investigate the role of P2X7 receptor (P2X7r) in osteogenic differentiation of human periodontal ligament stem cells (hPDLSCs). METHODS: hPDLSCs were isolated from the premolars collected in the First Affiliated Hospital of Guiyang University of Traditional Chinese Medicine, and divided into four groups. Group A was cultured in conventional medium, group B was cultured in osteogenic induction medium, group C was cultured in osteogenic induction medium + 100 nmol/L adenosine triphosphate (ATP) solution, and group D was cultured in osteogenic induction medium + 100 nmol/L P2X7 receptor specific antagonist KN-62. After 7 days, alizarin red staining was used to observe the osteogenic effect of hPDLSCs in each group. The mRNA expression of osteocalcin (OCN), RUNX2 and P2X7r in hPDLSCs was detected by real-time PCR reaction (RT-PCR). The data were processed by SPSS 22.0 software package. RESULTS: Alisarin red staining showed that the morphology of hPDLSCs cells in group B and group C was significantly changed. The pale calcified nodules in group C were significantly more than those in group B, while very few calcified nodules were found in group A and group D. The mRNA expression of OCN, RUNX2 and P2X7r in hPDLSCs were the highest in group C, followed by group B(P<0.05), and no difference was found between group A and group D(P>0.05). CONCLUSIONS: P2X7 receptor can promote osteogenic differentiation of human periodontal ligament stem cells after being activated by ATP, which may provide a new direction for clinical treatment of periodontitis.