降钙素经ERK-MAPK信号通路调控成骨细胞核心结合因子a1mRNA表达

Thyrocalcitonin regulates the cbfa1mRNA expression of osteoblasts via signal pathway of ERK-MAPK

目的研究降钙素对成骨细胞核心结合因子a1(cbfa1)mRNA表达情况以及细胞外信号调节激酶(ERK)信号通路在这一过程中的作用。方法取24 h内新生SD大鼠颅骨培养成骨细胞,分别加入不同浓度降钙素(0.01、0.1、1 ng/mL)和一定浓度ERK特异性抑制剂U0126进行干预,应用RT-PCR技术检测成骨细胞cbfa1 mRNA的表达情况;应用Western Blot-ting技术检测phos-ERK 1/2蛋白表达情况;采用Independent-Samples检验法分析比较各组间总体均值差异。结果加入0.01、0.1、1 ng/mL的降钙素干预后,成骨细胞表面cbfa1mRNA的表达随降钙素浓度的增加而增强,且中、高浓度组与空白对照组比较差异具有非常显著意义(P<0.01),此外降钙素刺激了phos-ERK1/2蛋白的表达。U0126可阻断以上所有效应。结论降钙素可上调成骨细胞cbfa1mRNA的表达,且ERK-MAPK信号通路参与了此过程。

Objective To observe the effect of thyrocalcitonin on the cbfa1 mRNA expression of osteoblasts and the effect of ERK-MAPK in the above process. Methods Isolate the osteoblasts from craniums of neonate rats within 24 hours after its birth and culture the osteoblasts in vitro. The second generation osteoblasts were co cultured with thyrocalcitonin at different concentrations： blank group, 0.01 ng/mL calcitonin group, 0.1 ng/mL calcitonin group, 1 ng/mL calcitonin group, and another 1 ng/mL calcitonin group were added with U0126, a specific inhibitor of ERK-MAPK, in advance. The level of cbfalmRNA in different groups were measured by RT-PCR and the phos-ERK1/2 expression of OB was analyzed by western blotting. Results Calcitonin can improve the expression of cbfal mRNA in dose-dependent manner. The effect of the 0.1 ng/mL calcitionin group and the 1 ng/mL calcitonin group had significant effects（P〈 0.01 ）; The expression of the phospho-ERK1/2 was also related to the calcitionin concentration. Moreover, all the effects above were blocked by U0126. Conclusion Calcitonin improves the expression of cbfa1mRNA via the signal pathway of ERK-MAPK.