中文摘要：

目的探讨姜黄素对神经干细胞内Wnt／β-catenin信号通路的影响。方法选择孕14．5d的SD大鼠，取胚鼠大脑前端2／3部分组织，提取神经干细胞。培养并传代3次时，进行细胞免疫荧光学鉴定；同时换用只添加2％B27的Neurobasal培养基连续培养细胞，并设置空白对照组、IWR-1（Wnt信号通路特异性阻断剂10μmol／L）处理组、姜黄素500nmol／L组、IWR-1＋姜黄素500nmol／L组（先添加IWR-1，20min后再加入姜黄素）、DMSO组。细胞培养3d时，采用Westernblot方法检测各组wnt3a、β-catenin蛋白表达水平变化，采用RT-PCR方法检测各组wnt3a、β-catenin的mRNA表达量变化。结果Westernblot结果显示：对培养第3代的细胞干预3d后，姜黄素组wnt3a、β-catenin表达量较其他各组明显升高（P〈0．05），IWR-1处理后其表达水平明显降低（P〈0．05）；姜黄素联合IWR-1处理细胞后wnt3a、β-catenin表达量明显减少（P〈0．05）；DMSO组表达量接近空白对照组。RT—PCR结果显示：与空白对照组比较，姜黄素组wnt3a及β-cate—nin基因表达水平明显上调（P〈0．05），而IWR-1组wnt3a及β-catenin基因表达水平明显下降（P〈0．05），总体变化趋势与Westernblot结果一致。结论初步证明姜黄素可激活wnt信号通路，由此推测姜黄素与经典的Wnt／β-catenin信号通路密切相关。

英文摘要：

Objective To investigate the effect of curcumin on expression of Wnt/β-catenin signaling pathway in neural stem cells in vitro. Methods Neural stem cells were isolated from anterior two-thirds brains of fetal Sprague-Dawley （SD） rats （ 14.5 d after pregnancy）. The neural stem cells were passaged for 3 times by half media replacement and identified by cellular immunofluorescence assay. After 3 passages, cells were seeded in the media without bFGF or EGF. Then, cells were treated in different groups： control group, IWR-1 （a specific inhibitor to Wnt signaling pathway, 10 μmol/L） group, 500 nmol/L curcumin group, IWR-1 ＋ curcumin 500 nmol/L group and DMSO group. We measured Wnt3a and β-catenin expression levels by Western blotting and RT-PCR separately. Results Western blotting results showed that Wnt3a and β-catenin expression levels had significant increases in the curcumin group （P 〈 0. 05 ） , but were decreased in the IWR-1 group and IWR-1 ＋ cureumin group （P 〈 0. 05 ）. RT-PCR results showed that the expression levels of Wnt3a and β-catenin were increased in the curcumin group but decreased in the IWR-1 group （ P 〈 0. 05 ） , showing similar change pattern to the Western blot results. Conclusion Curcumin activates the classic Wnt/β-catenin signaling pathway in neural stem cells .