Wnt3a对骨髓间充质干细胞成软骨分化的影响

Effect of Wnt3a on chondrogenic differentiation of mesenchymal stem cells

[目的]探讨Wnt3a基因对骨髓间充质干细胞（BMSCs）成软骨分化的影响。[方法]分离培养大鼠骨髓间充质干细胞（BMSCs）,携带Wnt3a及阴性对照基因（Mock）的慢病毒感染骨髓间充质干细胞,构建过表达Wnt3a骨髓间充质干细胞;采用甲苯胺蓝染色及QPCR观察Wnt3a对骨髓间充质干细胞成软骨分化能力的影响;使用MTT法观察Wnt3a对骨髓间充质干细胞增殖能力的影响。[结果]在0~72 h内,实验组MTT法检测吸光值明显大于对照组（P〈0.05）;BMSCs体外成软骨诱导后,实验组细胞团明显小于对照组,且甲苯胺蓝染色较浅;实验组与对照组比较,成软骨指标Col2A1、Aggrecan和SOX9的m RNA表达降低（P〈0.05）。[结论]Wnt3a可促进骨髓间充质干细胞增殖,但抑制了骨髓间充质干细胞的成软骨分化。

[Objective]To evaluate effect of Wnt3 a gene transfection by lentivirus carrier on chondrogenic differentiation of bone marrow mesenchymal stem cells（ BMSCs）. [Method]BMSCs from the rat were isolated and cultured,subsequently infected by lentivirus vector inserted Wnt3a- expressing coding sequence to establish an over- expression of Wnt3 a model,while the Mock- expressing coding sequence was used as control. Toluidine blue staining and quantitative polymerase chain reaction（ QPCR） were utilized to evaluate effect of Wnt3 a on chondrogenic differentiation,additionally MMT assay was used to observe cell proliferation and cell survival. [Result]The MTT showed that Wnt3 a enhanced proliferation of BMSCs. Compared with BMSCs infected with the control lentivirus,elevated expression of Wnt3 a in BMSCs decreased the accumulation of matrix proteoglycans,which was shown by toluidine blue staining,and decreased expression of chondrogenesis related factors,such as level of m RNAs of COL2A1,aggrecan,and SOX9. [Conclusion]Over- expression of Wnt3 a increases MSC proliferation,however,inhibits chondrogenesis of BMSCs.