氯化锂通过激活Wnt信号通路促进神经干细胞增殖

摘要

目的：观察氯化锂（LiCl）作用于神经干细胞（NSCs）后对细胞周期等生物学性状的影响以及经LiCl处理过的神经干细胞在分化过程中 Wnt信号通路的主要信号分子β-catenin、GSK-3β的表达改变，评估LiCl激活Wnt信号通路后对NSCs增殖和分化的影响。方法应用分离培养的NSCs体系，流式细胞仪检测不同浓度的LiCl（1、5、10、100mmol/L）处理48h后NSCs细胞周期等生物学性状改变，Western Blot检测LiCl处理后的NSCs中β-catenin、GSK-3β的表达以及动态变化。结果 LiCl处理后的NSCs体系细胞团块分散，呈悬浮状态生长，并能抑制血清诱导下的干细胞分化，分化细胞贴壁时间明显延长。流式细胞仪检测表现为S期、G2/M期细胞数百分比的增加和G0/G1期细胞数百分比的相对减少，其效应呈现一定的剂量依赖关系（ P＜0.01）。Western Blot检测显示NSCs中的β-catenin分子在LiCl处理后表达明显增强，GSK-3β分子的表达明显下调，表现出正相关的量效关系（P＜0.01）。结论 LiCl通过激活Wnt信号通路能促进培养NSCs的增殖，抑制干细胞分化，其作用可能与胞内效应分子β-catenin的表达增多有关。%Objective We investigated the effects of lithium chloride on the cell dynamic changes of NSCs and the dynamic expression changes of β-catenin and Gsk-3β in the proliferation and differentiation process of NSCs treated with lithium chloride .The aim was to evaluate the effect of lithium chloride on the proliferation and differ-entiation process of NSCs by triggering the Wnt signaling pathway .Methods The cell dynamic changes of NSCs treated with different concentration lithium chloride were examined using flow cytometry .The dynamic expression changes of Wnt signaling molecules in the proliferation and differentiation process of NSCs treated with lithium chloride was detected by Western blotting .Results It was observed that the NSCs treated with lithium chloride (LiCl) were usually floated and much dispersed in the media .This effect was much strong in the higher concentra-tion group than that of the lower ones .It was detected that the proportion of G0/G1 phase NSCs declined gradually accompanying the increased concentration of lithium chloride .In the meantime ,the percentage of S as well as G2/M phase cells showed an increasing trend ( P<0 .01 ) .Western blotting results revealed β-catenin expression in-creased gradually whereas Gsk-3β decreased gradually ( P< 0 .01 ) .Conclusion This results indicated that the effect of LiCl in promoting proliferation ability of NSCs and preventing them from differentiating was at least partly by triggering the Wnt signaling pathway and activation of β-catenin signaling molecules .