蛋白激酶C信号通路在温石棉致肺成纤维细胞的细胞周期和凋亡改变中的作用

The role of protein kinase C signal transduction pathways in the changes of both cell cycle and apoptosis of human embryonic pulmonary fibroblast induced by chrysotile

目的 探讨蛋白激酶C(PKC)信号通路与温石棉致人胚肺成纤维细胞 (HEPF)的细胞周期及细胞凋亡改变的联系。方法 利用流式细胞技术测定PKC的抑制剂或激活剂对温石棉处理兔肺泡巨噬细胞 (AM)的培养上清液致HEPF的细胞周期和凋亡改变的影响。同时设立空白对照、正常对照 (不加粉尘的AM)、阴性对照 (标准TiO2 )和阳性对照 (标准SiO2 )。结果 温石棉处理AM的上清液刺激HEPF增殖时 ,HEPF的G2 /M期细胞百分比为 7.2 % ,高于各对照组 ,而细胞凋亡百分率为 3.5 % ,低于各对照组 ,差异均有显著性 (P <0 .0 1) ;PKC抑制剂C2 5H2 4 N4 O2 使温石棉所致HEPF增殖时的S期细胞百分比由 37.8%减少到2 7.3% ,凋亡百分率由 3.5 %增加到 2 2 .7% ,差异均有显著性 (P <0 .0 1) ,而PKC激活剂PMA能使此S期细胞百分比增加。结论 温石棉所致HEPF增殖时的细胞周期变化与其上游PKC信号通路有关 。

Objective To explore the relationship between protein kinase C(PKC) signal transduction pathway and the changes of both cell cycle and apoptosis of human embryonic pulmonary fibroblast(HEPF) induced by chrysotile. Methods Flow cytometry to measure changes of both cell cycle and apoptosis of HEPF induced by the supernatants of chrysotile treated rabbit alveolar macrophage(AM) was used,and different controls:blank control,normal control(AM),negative (TiO 2) and positive(SiO 2) control were set up. Results In the process of proliferation of HEPF stimulated by the supernatant of AM treated by chrysotile,the percentage of the cells of G 2/M phase of HEPF in chrysotile group was 7.2%,higher than that in all controls;and the apoptosis percentage was 3.5% ,significantly lower than that in all controls( P <0.01).PKC inhibitor(C 25 H 24 N 4O 2) made the percentage of cells of S phase decreased from 37.8% to 27.3%( P <0.01) and apoptosis percentage increased from 3.5% to 22.7%( P <0.01),but PKC activator(PMA) made the percentage of S phase cells increased. Conclusion The change of cell cycle in HEPF proliferation induced by chrysotile was related to the up stream PKC signal pathway. The role of PKC activator or inhibitor was realized by primarily regulating DNA synthesis during S phase and inducing apoptosis of cell.