脂联素通过调节BMP信号通路促进骨髓干细胞成骨分化

目的 研究脂联素（adiponectin, ApN）对骨髓间充质干细胞（bone marrow mesenchymal stem cells, BMSCs）成骨分化的作用，并探讨其可能的机制。方法 体外培养BMSCs，构建ApN过表达质粒及干扰质粒，转染至BMSCs中。将BMSCs随机分为5组：对照组、过表达组、过表达空载组、干扰组和干扰空载组。茜素红染色观察各组细胞钙化沉积。碱性磷酸酶（alkaline phosphatase, ALP）染色观察各组细胞成骨分化能力。qRT-PCR检测ApN受体、骨形态发生蛋白（bone morphogenetic protein, BMP）信号通路及成骨相关基因表达情况。结果 与对照组相比，过表达组BMSCs中钙化沉积和ALP阳性表达增多，AdipoR1、AdipoR2、BMP2、RUNX2、Smad1和Smad5 mRNA表达量显著升高（P<0.05）；干扰组BMSCs中钙化沉积和ALP阳性表达减少，AdipoR1、AdipoR2、BMP2、RUNX2、Smad1和Smad5 mRNA表达量显著降低（P<0.05）。结论 ApN可能通过上调BMP信号通路促进BMSCs成骨分化。

Adiponectin promotes osteogenic differentiation of bone mesenchymal stem cells by regulating BMP signaling pathway

Objective To investigate the effect of adiponectin (ApN) on osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) and to explore its possible mechanism. Methods BMSCs were cultured in vitro. ApN over-expression and interfering plasmids were constructed and transfected into BMSCs. The calcification deposition of cells in each group was observed with Alizarin red staining. The osteogenic differentiation ability of cells in each group was observed with alkaline phosphatase (ALP) staining. The expression of ApN receptors, and bone morphogenetic protein (BMP) signaling pathway and osteogenic related genes were detected using qRT-PCR. Results Compared to those in the control group, calcification deposition and ALP positive expression increased, the mRNA expression levels of AdipoR1, AdipoR2, BMP2, RUNX2, Smad1, and Smad5 increased significantly in the over-expression group (P<0.05). Calcification deposition and ALP positive expression decreased, and the mRNA expression levels of AdipoR1, AdipoR2, BMP2, RUNX2, Smad1, and Smad5 decreased significantly in the interference group (P<0.05). Conclusion ApN may promote osteogenic differentiation of BMSCs by up-regulating BMP signal pathway.