三丁基过氧化氢诱导WI-38细胞衰老的细胞周期调控机制

目的：探讨三丁基过氧化氢(t-BHP)诱导WI-38细胞衰老的细胞周期调控机制。方法： 从30代开始，隔代用t-BHP作用WI-38细胞4次，每次1 h，诱导细胞衰老，从细胞超微结构、细胞周期分析和β-半乳糖苷酶细胞化学染色观察衰老细胞的特点，同时用Western blotting方法检测细胞周期调控蛋白CDK4、CDK2、cyclin D1、cyclin E 、p21和p16的表达程度。 结果：100 μmol/L t-BHP作用4次后，WI-38细胞出现衰老的特征，细胞增殖分裂停止，细胞体积增大、胞体变平、次级溶酶体增多，同时G1期细胞比例增加，β-半乳糖苷酶染色阳性细胞数增加，提示t-BHP能有效地诱导细胞衰老。t-BHP作用后CDK4、CDK2、cyclin E 表达下降，cyclin D1、p21和p16表达增加。 结论： t-BHP有诱导细胞衰老的作用，其机制可能与通过调节细胞周期调控分子的表达有关。

Cell cycle in aging model of WI-38 cells induced by tert-butylhydroperoxide

AIM: To investigate the mechanism of cell cycle in aging model induced by tert-butylhydroperoxide(t-BHP).METHODS: From the 30th population doubling(PD), WI-38 cells were exposed for 1 h to t-BHP at every two PDs and four stresses were induced. The cell morphology and ultrastructure, cell cycle assay and β-galactosidase cytochemistry staining were used to evaluate cell senescence. Then the levels of CDK4, CDK2, cyclin D1, cyclin E, p21 and p16 protein were detected by Western blotting.RESULTS: After four times treated with 100 μmol/L t-BHP, the proliferation and division in WI-38 cells were ceased, which showed that cell became larger and flat, the number of secondary lysosome and activity of SA-β-galactosidase were increased. In addition, the percentage of cells in the G1 phase was decreased. Furthermore, it showed that the protein levels of CDK4, CDK2 and cyclin E was reduced and cyclin D1, p21 and p16 was elevated.CONCLUSION: t-BHP induces senescence in WI-38 cells. The possible mechanism is that t-BHP can change the expression of proteins related with cell cycle.