间断性PTHrP对成牙骨质细胞凋亡及矿化的影响

Influence of intermittent PTHrP stimulation on apoptosis and cementogenesis in cementoblasts

目的探讨间歇性甲状旁腺激素相关蛋白(parathyroid hormone related protein,PTHrP)刺激在成牙骨质细胞中对细胞凋亡和成牙骨质矿化相关蛋白和细胞因子表达的影响。方法应用成牙骨质细胞OCCM-30,使用PTHrP(1-36)、甲状旁腺激素I型受体(parathyroid hormone type I receptor,PTH1R)阻断剂PTHrP(7-34)对细胞进行间歇性刺激,间歇性给药模式包含3个周期,48 h/周期,分为对照组、PTHrP(1-36)组及PTH1R阻断剂组。采用流式细胞术检测细胞凋亡;采用茜素红染色观察矿化功能;采用real-time PCR和Western blotting法检测细胞内成牙骨质矿化相关蛋白-骨桥素(osteopontin,OPN)、I型胶原蛋白(collagen-1,COL-1)及成牙骨质相关细胞因子I型胰岛素样生长因子-1(insulin like growth factor-1,IGF-1)的基因表达及蛋白质表达。结果间断性PTHrP抑制成牙骨质细胞凋亡,PTH1R阻断剂促进成牙骨质细胞凋亡(P<0.05);PTHrP间断性刺激能够显著增加成牙骨质细胞内OPN、COL-1、IGF-1基因及蛋白表达(P<0.05);PTH1R阻断剂抑制成牙骨质细胞内OPN、COL-1、IGF-1基因及蛋白表达(P<0.05)。结论间断性PTHrP可通过与成牙骨质细胞上PTH1R相互作用抑制细胞凋亡,促进成牙骨质细胞矿化以及相关蛋白和细胞因子的表达。

Objective To investigate the effect of intermittent parathyroid hormone related protein(PTHrP)on apoptosis and the expression of cementum mineralization related proteins and cellular factors in cementoblasts.Methods OCCM-30 cells were stimulated intermittently with PTHrP(1-36)and PTH1R antagonist PTHrP(7-34).The intermittent administration consisted of three cycles,48 hours/cycle.The cells were divided into control group,PTHrP(1-36)group and PTH1R blocker group.Cell apoptosis was detected by flow cytometry,osteopontin(OPN),collagen(COL-1)and insulin-like growth factor-1(IGF-1)were detected by real-time PCR and Western blotting.Results Intermittent administration of PTHrP inhibited the apoptosis of cementoblasts and PTH1R antagonist promoted the apoptosis(P<0.05),intermittent PTHrP significantly increased the mRNA and protein expression of OPN,COL-1 and IGF-1 in cementoblasts(P<0.05)compared with control group.PTH1R antagonist inhibited the mRNA and protein expression of OPN,COL-1 and IGF-1 in cementoblasts(P<0.05).Conclusion Our study indicates that intermittent PTHrP could inhibit apoptosis and promote the cementogenesis by interacting with PTH1R in cementoblasts.