【摘要】 目的:了解经典Wnt信号通路在骨髓间充质干细胞(BMSCs)加载牵张中的作用。方法:分离培养大鼠BMSCs,通过自行研制的细胞加载装置,对BMSCs施加机械张应力刺激。用实时荧光定量RT-PCR与Western印迹检测Wnt3A、β-catenin与Lef-1的表达,同时检测BMSCs细胞增殖及骨向分化转录因子Runx2与成骨因子碱性磷酸酶(ALP)的变化情况。所得数据应用SPSS19.0软件包进行配对t检验。结果:在牵张力刺激下,经典Wnt信号通路的3个关键分子Wnt3A、β-catenin与Lef-1基因表达显著增强(P<0.05)。BMSCs的增殖、Runx2表达以及ALP活性也在加力后增强(P<0.05)。结论:张应力加载激活了经典Wnt信号通路,并刺激BMSCs增殖与骨向分化,提示Wnt/β-catenin参与了牵张成骨的分子调控过程。更多还原

【Abstract】 PURPOSE:To observe the role of canonical Wnt/β-catenin signal pathway in the stretched rat bone marrow mesenchymal stem cells(BMSCs). METHODS: BMSCs were isolated from SD rats and cultured in vitro. A custom-made apparatus was used to perform a mechanical stretch on BMSCs. mRNA and protein expression of Wnt3A, β-catenin, Lef-1 and Runx2 were detected by RT-PCR and Western blot analysis. Cellular proliferation and ALP activity of BMSCs were also examined. All data collected were dealt with paired t-test using SPSS 19.0 software package. RESULTS:Under mechanical stimulation, cell proliferation, ALP activity and expression of Wnt3A, β-catenin, Lef-1 and Runx2 were all significantly up-regulated in stretched BMSCs when compared with the controls(P<0.05). CONCLUSIONS:The activation of Wnt/β-catenin signal pathway is related to the mechanical stimulation on BMSCs. The mechanical stretch can promote cellar proliferation, up-regulate ALP activity and induce osteogenic differentiation of the BMSCs. Supported by National Natural Science Foundation of China(81271106).更多还原