FGF-2与BMP-2在颅缝细胞成骨分化中的相互作用

Crosstalk of FGF-2 and BMP-2 in Osteoblastic Differentiation of Cranial Suture Cells

目的探讨碱性成纤维生长因子2(FGF-2)与骨形成蛋白2(BMP-2)在颅缝细胞成骨分化中的相互作用及其机制。方法获取新生SD大鼠颅骨矢状缝及冠状缝处颅缝细胞,在培养体系中添加FGF-2,观察BMP-2表达情况。同时在培养体系中添加FGF-2及BMP-2,ALP染色、矿化染色、qPCR检测成骨标志物,观察颅缝细胞成骨分化情况。添加BMP-2抑制剂Noggin后,观察颅缝细胞成骨分化的转归。结果FGF-2可促进BMP-2在颅缝细胞中的表达,呈浓度依赖性及时间依赖性;两者同时作用颅缝细胞可促进其晚期成骨分化,抑制其早期成骨分化。Noggin阻断BMP-2信号通道后,FGF-2及FGF-2+BMP-2促进颅缝细胞晚期成骨分化作用均减弱。结论BMP-2是FGF-2调控颅缝细胞晚期成骨分化不可或缺的下游因子。

Objective To explore the interaction of FGF-2 and BMP-2 in osteoblastic differentiation of calvarial suture cells. Methods Neonatal calvarial suture cells of SD rat were harvested. FGF-2 was added into cell cultures and BMP-2expression in cranial suture cells was observed. Meanwhile, FGF-2 and BMP-2 were both added into cell cultures and the osteoblastic differentiation of cranial suture cells was observed by ALP staining, mineralized nodule staining and q PCR. Then Noggin was added to observe the changes of cells＇ osteoblastic differentiation. Results BMP-2 expression increased in a time-dependent manner after the cells treated with FGF-2 and increased in a dose-dependent manner up to 50 ng/ml FGF-2, after which BMP-2 expression reached a plateau; After FGF-2 and BMP-2 co-stimulation, the expression of early marker of osteoblast differentiation（COL-1） was decreased while the expression of late markers（ALP, OC and BSP） were increased to accelerate mineralization. The natural BMP antagonist Noggin inhibited the expression of FGF2-induced OC and BSP by1.40-fold and 1.41-fold respectively, and inhibited the expression of FGF2- and BMP2-induced OC and BSP by 1.26-fold and 1.20-fold respectively. Conclusion BMP2 is a downstream target of FGF-2, and BMP-2 signals are required for FGF-2-dependent induction of later-stage osteoblast differentiation in cranial suture cells.