手霉素通过阻断PI3K／Akt信号通路诱导U937白血病细胞凋亡

Manumycin-induced apoptosis in U937 human myeloid leukemia cells via blocking PI3K/Akt signaling pathway

目的:探讨手霉素对U937白血病细胞的作用及其机制。方法:2μmol/L的手霉素处理U937白血病细胞不同时间,分别使用Annexin V/PI试剂及ROS检测试剂标记细胞后,应用流式细胞术检测细胞凋亡及细胞内ROS生成,免疫印迹术检测PI3K、P-Akt、Akt等蛋白的表达。结果:与0 h对照组相比,随着处理时间的延长,手霉素诱导的U937细胞凋亡(P<0.05)及ROS生成逐渐增加(P<0.05),对PI3K/Akt信号通路活化的抑制逐渐增强。N-乙酰基-L-半胱氨酸(NAC)(能有效抑制ROS产生的物质)可以阻断手霉素对U937细胞内PI3K/Akt信号通路的抑制及手霉素诱导的U937细胞凋亡。结论:手霉素通过诱导ROS产生进而抑制PI3K/Akt信号通路活化来诱导U937细胞凋亡。

Objective To explore the effects of manumycin on U937 cells and its mechanisms. Methods Apoptosis was detected by flow cytometry using annexin V and propidium iodide （PI） after treatment with manumycin （2 μmol/L） for different time. The reactive oxygen species （ROS） was detected by flow cytometry using Reactive Oxygen Species Assay Kit. The expressions of PI3K, P-Akt and Akt were detected by Western blotting. Results Compared with the 0 h treatment, manumycin treatment resulted in apoptosis （P 〈 0.05 ） and ROS generation （P 〈 0.05） gradually in U937 cell lines. Furthermore, manumycin also inhibited the activation of phosphatidylinositol-3 kinase （PI3K）/Akt pathway. Moreover, NAC could decrease manumycin-induced ROS generation and inhibit the effects of manumycin on the PI3K/Akt pathway and protect U937 cells from apoptosis induced by manumycin. Conclusion Manumycin induces apoptosis in U937 human leukemia cells through the regulation of the PI3K/Akt pathway and ROS production plays a critical role in the progress.