PI3K/AKT途径在HGF介导肝干细胞抗凋亡调控中的作用  

Role of MAPK and PI3K pathways in hepatocyte growth factor-mediated anti-apoptosis

作　　者：姚鹏[1] 杨晓明[2] 胡大荣[1] 

机构地区：[1]北京军区总医院肝病研究所,北京100700 [2]军事医学科学院放射研究所

出　　处：《中华微生物学和免疫学杂志》2005年第2期89-93,共5页Chinese Journal of Microbiology and Immunology

摘　　要：目的　研究PI3K(磷脂酰肌醇 3激酶 )和MAPK(丝裂原活化蛋白激酶 )途径如何参与肝干细胞的凋亡调控 ;探讨PI3K和MAPK信号途径在HGF介导的抗凋亡信号中的调控。方法　用大鼠肝干细胞系WBF 344细胞进行实验 ;用流式细胞仪检测细胞及DNA凝胶电泳及流式细胞仪检测细胞凋亡 ;用Westernblot方法检测磷酸化MAPK及PI3K蛋白的表达。结果　发现TNF α对ActD致敏的WBF 344细胞能诱导凋亡 ,并且这种细胞凋亡呈现剂量效应关系 ;HGF对ActD TNF α诱导WBF 344细胞凋亡具有保护作用 ,并且这种保护作用呈剂量效应关系 ;Westernblot结果显示 ,在WB细胞 ,HGF确实能够激活ERK、p38MAPK、PI3K AKT信号转导途径 ;进一步用特异的抑制剂阻断ERK及p38MAPK途径后 ,并不能改变HGF对TNF α诱导凋亡的拮抗作用 ,而阻断PI3K AKT途径后 ,HGF的抗凋亡作用被抑制。结论　TNF α能诱导ActD致敏的肝干细胞发生凋亡 ,而HGF则对这种细胞凋亡有明显的拮抗作用 ;ERK1 2和p38MAPK途径的激活并不参与HGF介导的抗凋亡作用 ,HGF的抗凋亡作用是通过PI3K途径转导的。Objective To investigate the role of MAPK, PI3K/AKT pathways in HGF dependent protected effect on ActD/TNF-α induced apoptosis in a liver stem like cell line WB F-344 cells. Methods WB cell were exposed to ActD, TNF-α or/and HGF. Apoptosis were evaluated by flow cytometry (FCM) and DNA fragmentation; the phospho-MAPK were detected by Western blot. Results The results show that ActD/TNF-α can induced apoptosis in WB F-344 cells, but TNF-α does not induce a significant apoptosis alone. The apoptosis is detected at 9 h after adding ActD/TNF-α and achieves the peak at 48 h. Furthermore, we find that HGF can significantly reduce the apoptosis of WB cell induced by ActD/TNF-α and it enhanced with increase of HGF concentration. Our results also show that the anti-apoptosis effects of HGF are inhibited when PI3k pathway is abolished by the specific inhibitor Wartmanner, but not inhibited when MAPK pathway is abolished by inhibitor U0126. Conclusion Apoptosis of WB cells can be induced by ActD/TNF-α, and HGF can protect the WB cells from ActD/TNF-α induced apoptosis. Although HGF can activate both the PI3K and MAPK pathways, the anti-apoptosis effect of HGF occurs via a PI3K pathway and is not dependent on the MAPK pathway.

关 键 词：HGF 凋亡调控 肝干细胞 AKT 介导 流式细胞仪检测 Western 丝裂原活化蛋白激酶 磷脂酰肌醇3激酶 剂量效应关系 MAPK途径 TNF-α 抗凋亡作用 DNA凝胶电泳 p38MAPK 细胞凋亡 信号转导途径 ERK1/2 PI3K途径 blot 诱导凋亡 

分 类 号：R346[医药卫生—基础医学]