骨形态发生蛋白2介导甲状旁腺素促进成骨细胞分化的实验研究

Parathyroid hormone stimulate osteoblast differentiation by up-regulation of BMP2 expression and function

目的探讨骨形态发生蛋白2(BMP2)在甲状旁腺素(PTH)促进成骨细胞分化过程中的重要介导作用。方法培养MC3T3-E1细胞,分为4组:1)盐水对照组;2)PTH组;3)6-[4-[2-(1-哌啶基)乙氧基]苯基]-3-(4-吡啶基)吡唑并[1,5-a]嘧啶(Dorsomorphin)组;4)PTH+Dorsomorphin组。Real-time PCR法和Westernblot方法检测细胞BMP2、BMP2下游基因和成骨因子的表达,碱性磷酸酶(ALP)染色方法检测细胞ALP的活性;双荧光素酶报告基因检测方法检测12xSBE-OC荧光素酶的活性。结果 :PTH组BMP-2、成骨因子的表达及其12xSBE-OC荧光素酶的活性,明显高于盐水对照组。Dorso-morphin组和PTH+Dorsomorphin组BMP-2、BMP-2下游基因和成骨因子的表达,均明显低于盐水对照组;但其表达于两组间无明显差别。结论 BMP2介导PTH促进成骨细胞的分化,PTH可通过上调BMP2的表达,提高其功能,促进成骨细胞的成熟分化。

Objective To study the important role of BMP2 in the PTH-induced osteoblast differentiation. Methods MC3T3-E1 cells were divided into 4 groups： 1） Controls; 2） PTH treatment; 3） Dorsomorphin treatment; 4） PTH q-Dorsomorphin treatment. Gene and protein expression levels of BMP2, BMP2 downstream genes and osteoblastic genes and protein expressions were detected by Real-time PCR and Western blot respectively. Alkaline phosphatase （ALP） staining was performed to detect ALP activity. 12xSBE-OC luciferase activity was measured using dual luciferase reporter assays. Results The expression level of BMP2 and osteoblastic marker genes was higher in the PTH group than in controls. PTH also increases 12xSBE-OC luciferase activity significantly. In the other hand, the expression of BMP2, BMP2 downstream genes and o＇steoblastic genes was lower in Dorsomorphin and PTH q-Dorsomorphin group, than in controls. However, the expression was similar in Dorsomorphin and PTH--Dorsomorphin groups. Conclusion PTH stimulates osteoblast differentiation by up-regulating BMP2 expression and function.