【摘要】 研究不同浓度的脑源性神经营养因子(BDNF)在体外诱导SH-SY5Y细胞分化时对G1期细胞周期相关蛋白表达的影响。采用全反式维甲酸(RA)和低(1ng/ml)、中(10ng/ml)、高(100ng/ml)三种不同浓度BDNF在无血清培养液中相继诱导SH-SY5Y细胞分化,形成均一的具有神经元形态的细胞。以实时定量RT-PCR法检测G1期细胞周期相关蛋白(包括cdk4,cdk6,cyclin D1,Cyclin E,p16和p27)的mRNA水平的表达变化。结果显示:不同浓度的BDNF处理后,Cdk4mRNA的表达水平均低于未分化细胞组(P<0.05);Cdk6和Cyclin D1的mRNA表达水平与RA组比较显著降低(P<0.05),Cyclin E和p16的mRNA表达水平仅在高浓度BDNF处理后明显降低,与未分化组比较P<0.05,p27的mRNA表达水平无显著变化。以上结果提示BD-NF在诱导SH-SY5Y细胞分化的同时无意促使其再进入细胞周期。同时,用RA预处理5d后改换BDNF培养SH-SY5Y细胞,可使细胞展现出成熟神经细胞的形态,是体外研究某些脑疾病的理想细胞模型。更多还原

【Abstract】 The aim of this study is to investigate the effec of BDNF on the expression of cell cycle-related proteins of G₁ phase of differentiated SH-SY5Y cells in vitro. Sequential exposure of SH-SY5Y cells to retinoic acid （RA） and various contents （1 ng, 10 ng, 100 ng/ml） of brain-derived neurotrophic factor （BDNF） in serum-free medium yields homogeneous population of cells with neuronal morphology. Real time RT-PCR was carried out to determine the level of mRNA encoding cell cycle-related proteins in G₁ phase. The results indicated that the level of Cdk4 mRNA was lower than that of undifferentiated cells （P<0.05） and the levels of Cdk6 mRNA and cyclin D1 in all BDNF groups were downregulated significantly comparing to those of RA group（P<0.05） The levels of cyclin E mRNA and p16 mRNA were decreased only in 100 ng BDNF group comparing to those in undifferentiated group（P<0.05）; No change was found in the expression of p27 mRNA betwecn BDNF groups and control. The results suggest that BDNF can induce SH-SY5Y cells to differentiate rather than reentering to cell cycle. SH-SY5Y cells, which pretreated with RA for 5 days then switched to BDNF-containing, can be used to supply a model for studying some diseases of brain in vitro.更多还原