敌百虫对人成神经瘤细胞SH-SY5Y增殖与分化的影响

目的观察敌百虫（trichlorfon，TCL）的对神经细胞增殖与分化的影响。方法用敌百虫（0～500μmol／L）染毒SH-SY5Y细胞，分别作用24h和48h，MTT法测定细胞增殖，流式细胞术检测细胞周期；采用维甲酸（ATRA）诱导SH-SY5Y细胞分化，并用100μmol／L敌百虫染毒处理，观察细胞神经突起长出的长度及其与细胞体的大小之比，来判定神经元分化程度。结果敌百虫对细胞的增殖有显著的抑制作用，且显现剂量依赖相关和时间依赖相关。染毒24h和48h测得TCL对SH—SY5Y细胞的半数抑制浓度（IC50）分别是225μmol／L和177μmol／L。细胞诱导分化实验结果显示，对照细胞突起较长较多，而敌百虫处理神经细胞的突起则较少较短，提示敌百虫具有抑制神经突起生长的作用。流式细胞术分析表明，100μmol／L和200μmol／L敌百虫染毒24h或48h对SH-SY5Y细胞的运行周期产生显著影响，使细胞周期阻滞在G2／M期，但并没有使细胞产生凋亡。结论敌百虫可抑制神经突起的生长；敌百虫对SH—SY5Y细胞的增殖抑制与其对细胞周期的影响（阻滞细胞周期于G2／M期）有关。

Effect of Trichlorfon on Proliferation and Differentiation of SH-SY5Y Human Neuroblastoma Cells

Objective To investigate further the neurotoxicity of chemical insecticide trichlorfon （TCL） and to determine the effects of TCL on neuroblastoma cell proliferation and differentiation. Methods SH-SYSY ceils were treated with 0 - 500 μmol/L TCL for 24 h or 48 h, and the cell viability was determined using MTT assay. Cell differentiation was induced by 20μmol/L ATRA and cell was co-treated with 100μmol/L TCL,then,the neural process of long length and cell size ratio were observed to assess the level of cell differentiation using inverted microscope. The growth inhibitory effec of TCL （ 100 μmol/L,200 μmol/L） for 24 h or 48 h on cell cycle progression/apoptosis were assessed by Flow Cytometry. Results TCL significantly inhibited the proliferation and growth of SH-SYSY cells in a dose-effect and time-effect relationship. The 50% inhibiting concentration （ IC50 ） of TCL exposure for 24 h and 48 h were 225 μmol/L and 177 I.Lmol/L respectively. In addition, there were no increase of sub-G1 peak in all tested ceils,indicating the ceils did not undergo apoptosis even after 24 or 48 hour exposure to TCL. Cell differentiation assay found that TCL treatment of neural processes were less long than non-treated controls, suggesting TCL inhibiting the growth of axons. Flow Cytometry analysis showed that,TCL （100 μmol/L,200 μmol/L） had a significant impact on the cell cycle progression,arresting at the G2/M phase,compared with non-treated controls after 24 h of incubation. Conclusion TCL may be able to inhibit the growth of axons,The suppressive effect of TCL at high concentration was associated with G2/M stage arrest in SH-SYSY cells.