氯化锂对经血源性间充质干细胞增殖和神经分化的影响

摘要

目的：探讨Wnt／β-catenin通路激活剂氯化锂（LiCl）对经血源性间充质干细胞（MMCs）增殖和神经分化的影响。方法：CCK-8法检测不同浓度（0、4、10、20、40 mmol／L） LiCl作用4 d对MMCs增殖的影响，采用半定量PCR和Western blot法检测4 mmol／L LiCl对MMCs中β-catenin 表达的影响；采用免疫细胞化学检测对照组、诱导分化组（ DMSO和β-ME联合诱导分化）和4 mmol／L LiCl诱导组细胞中NF和NSE阳性细胞率，采用半定量PCR检测NF和NSE在转录水平的表达。结果：低浓度（4、10 mmol／L）LiCl促进MMCs增殖，高浓度（20、40 mmol／L）LiCl抑制MMCs增殖。与对照组相比，4 mmol／L LiCl处理可增加β-catenin蛋白的表达水平（t＝64．500，P＜0．001），而mRNA的表达水平无明显变化（t＝1．606，P＝0．183）。诱导分化组细胞中NF和NSE mRNA的表达水平及蛋白的阳性表达率升高（P＜0．05）；与诱导分化组相比，4 mmol／L LiCl诱导组NF和NSE mRNA的表达水平及蛋白的阳性表达率降低（P＜0．05）。结论：4 mmol／L LiCl可通过增强β-catenin蛋白的表达激活Wnt／β-catenin信号通路，促进MMCs的增殖；而在诱导分化过程中，LiCl 通过抑制NF和NSE在转录和蛋白水平的表达抑制MMCs向神经元分化。%Aim:To study the influence of lithium chloride(LiCl), a Wnt/β-catenin pathway activator, on the prolif-eration and differentiation of menstrual blood-derived mesenchymal stem cells ( MMCs) .Methods:After treatment with dif-ferent concentrations of LiCl (0,4,10,20,40 mmol/L) for 4 d, the proliferative activity of MMCs was detected by means of CCK-8 assay.After treatment with 4 mmol/L LiCl, the expression of β-catenin was examined by semi-quantitative PCR and Western blot.Then MMCs were allocated into control group , induction group and 4 mmol/L LiCl group, and the expres-sions of NF and NSE were detected by semi-quantitative PCR and immunocytochemistry .Results: Low concentrations (4, 10 mmol/L) of LiCl could promote the proliferation of MMCs , and high concentrations (20, 40 mmol/L) of LiCl could in-hibit the proliferation of MMCs .Compared with control group , 4 mmol/L LiCl could significantly increase the expression ofβ-catenin in protein level (t=64.500,P<0.001), but not in mRNA level(t=1.606,P=0.183).After induction, the expressions of NF and NSE positive cells increased both in protein level and mRNA level (P<0.05).Compared with in-duction group, 4 mmol/L LiCl could inhibit the expression of NF and NSE both in protein level and mRNA level ( P<0.05).Conclusion:The results suggest that 4 mmol/L LiCl may promote the proliferation of MMCs by activating Wnt /β-catenin pathway ,but inhibit the differentiation of MMCs into neurons by decreasing the expressions of NF and NSE in tran -scription and protein level .