论文部分内容阅读
目的研究周期机械拉伸加载对大鼠骨髓间充质干细胞增殖的影响及其相关力信号转导分子。方法应用周期机械拉伸加载装置研究不同参数的周期机械拉伸加载对大鼠骨髓间充质干细胞生长的影响。RT-PCR法检测c-fos mRNA表达的变化,Western blotting分析细胞外信号调节激酶(ERK1/2)磷酸化水平及c-fos蛋白表达的变化。结果适宜的机械拉伸加载可以明显促进大鼠骨髓间充质干细胞增殖,在频率1 Hz、形变量10%、拉伸15 min且静止6 h的条件下可以使细胞数量增加到对照组的1.4倍,c-fos mRNA和蛋白的表达显著增加。Western blotting检测证实,周期性机械拉伸加载明显促进ERK1/2磷酸化,却不影响ERK1/2总蛋白(t-ERK1/2)的表达水平。抑制剂PD98059显著抑制了机械拉伸对细胞增殖的促进作用,同时抑制拉伸诱导的ERK1/2磷酸化及c-fos基因和蛋白的表达水平。结论 ERK1/2信号分子的活化在周期性机械拉伸加载调控大鼠骨髓间充质干细胞增殖的过程中起着重要作用,且该通路可能通过转录因子的调节促进rBMSCs的增殖。
Objective To study the effect of cyclic mechanical tensile loading on the proliferation of rat bone marrow mesenchymal stem cells and its related signal transduction molecules. Methods Cyclic mechanical tensile loading device was used to study the effects of different mechanical parameters on the growth of rat bone marrow mesenchymal stem cells. The changes of c-fos mRNA expression were detected by RT-PCR. The phosphorylation of extracellular signal-regulated kinase (ERK1 / 2) and the expression of c-fos protein were analyzed by Western blotting. Results Appropriate mechanical tensile loading could significantly promote the proliferation of rat bone marrow mesenchymal stem cells. Under the condition of 1 Hz frequency, 10% deformation, 15 min stretch and 6 h rest, the number of cells could be increased to 1.4 Fold, c-fos mRNA and protein expression was significantly increased. Western blotting confirmed that cyclic mechanical tensile loading significantly enhanced ERK1 / 2 phosphorylation but did not affect the expression of ERK1 / 2 total protein (t-ERK1 / 2). Inhibitor PD98059 significantly inhibited the mechanical stretch on the promotion of cell proliferation, while inhibiting stretch-induced ERK1 / 2 phosphorylation and c-fos gene and protein expression levels. Conclusion Activation of ERK1 / 2 signaling plays an important role in the regulation of rat bone marrow mesenchymal stem cell proliferation by cyclic mechanical tensile loading, and this pathway may promote the proliferation of rBMSCs through the regulation of transcription factors.