乌索酸诱导Jurkat细胞凋亡及其机制的初步研究

Apoptosis of Jurkat Cells Induced by Ursolic Acid and Its Mechanison

本研究旨在探讨乌索酸(ursolic acid,UA)对Jurkat细胞的诱导凋亡作用及其分子机制,为UA应用于血液系统恶性肿瘤治疗提供理论依据。培养Jurkat细胞,用Water Solubility Tetrazolium-8(WST-8)法检测不同浓度UA对Jurkat细胞的细胞毒作用,观察caspase-9抑制剂对UA细胞毒作用的抑制情况;分别收集20、40μmol/L UA处理2小时和4小时的Jurkat细胞,用Annexin/PI双染色、流式细胞仪检测细胞凋亡率;收集不同浓度UA作用不同时间的Jurkat对数生长期细胞,提取蛋白,用Western blot分析caspase-9和-3及细胞色素C活化、Akt磷酸化情况。结果表明:UA能明显降低Jurkat细胞的生存率,能够诱导Jurkat细胞凋亡,caspase-9抑制剂能够抑制UA的细胞毒作用。在UA诱导Jurkat细胞凋亡过程中,caspase-9、caspase-3和细胞色素C被活化,Akt磷酸化受到抑制。结论:UA对Jurkat细胞具有明显的细胞毒作用,并能诱导其凋亡;UA诱导Jurkat细胞凋亡是通过线粒体途径实现的,其机制可能与抑制细胞生存因子Akt磷酸化过程相关。

The aim of this study was to investigate the apoptosis effect of Jurkat cells induced by ursolic acid （UA） and its molecular mechanism so as to provide the theoretical basis for treatment of hematological malignancies by using UA. The cytotoxic effect of different concentration UA on Jurkat cells and inhibitory effect of caspase-9 inhibiter on cytotoxicity of UA were assayed by using WST-8 method; the Jurkat ceils treated with 20 or 40 p^mol/L UA for 2 or 4 hours were collected and were stained by Annexin/PI, then the apoptosis rate of Jurkat cells was detected by flow cytometry ; the Jurkat cells in logarithmic growth phase were collected after treatment with different concentrations of UA for different times, the cell protein was extracted, then the activation of caspase-9, -3 and cytochrome C as well as phosphorylation level of Akt were determined by Western blot. The results indicated that the cytotoxic effect of UA on Jurkat cells was significant. UA induced apoptosis of Jurkat cells. Caspase-9, caspase-3 and cytochrome C were activated, and the phosphorylation of Akt was inhibited in the Jurkat cell apoptosis process induced by UA. It is concluded that the UA shows significant cytotoxic effect on Jurkat cells, UA can induce apoptosis of Jurkat cells through the mitochondria pathway. The mechanism may be associated with the inhibition of Akt phosphorylation.