鸦胆子苦醇通过TLR9-MyD88信号通路调控Hela细胞凋亡的机制研究

The Mechanism of Brucea javanica Regulating Hela Cell Apoptosis Through TLR9-My D88 Signaling Pathway

目的探究鸦胆子苦醇(Brusatol,BRU)通过TLR9-MyD88信号通路调控Hela细胞凋亡的分子机制。方法针对本实验室保存的Hela细胞,使用不同浓度(0、5.0、10.0、20.0、40.0、80.0 nmol·L^(-1))的鸦胆子苦醇处理细胞。并将Hela细胞分为Control组(正常培养的Hela细胞)、BRU-L组(使用10.0 nmol·L^(-1)的鸦胆子苦醇处理细胞)BRU-H组(使用20.0 nmol·L^(-1)的鸦胆子苦醇处理细胞)、BRU+pcDNA-NC组(转染pcDNANC+20.0 nmol·L^(-1)的鸦胆子苦醇)、BRU-H+pcDNA-TLR9组(转染pcDNA-TLR9+20.0 nmol·L^(-1)的鸦胆子苦醇)。使用细胞计数试剂盒(CCK-8)法和EdU法检测各组细胞增殖情况;TUNNEL染色法,经流式细胞仪检测细胞凋亡;蛋白免疫印迹(Western blot)检测各组细胞TLR9、MyD88、Bax、Bcl-2、Cleaved Caspase-3和Cleaved Caspase-9蛋白表达水平;流式细胞术检测细胞凋亡和线粒体膜电位检测试剂盒(JC-1)情况、ELISA检测各组细胞三磷酸腺苷(ATP)和活性氧基团(ROS)含量。结果与0 nmol·L^(-1)组比较,10 nmol·L^(-1)组细胞活存活率、IC50值开始显著降低(P<0.05)。不同浓度的BRU刺激细胞后,细胞增殖能力显著降低,且呈剂量依赖(P<0.05)。。与Control组比较,BRU-L、BRU-H组、BRU-H+pcDNA-NC组细胞5-乙炔基-2′-脱氧尿嘧啶核苷(EDU)阳性细胞率、缺口末端标记法(TUNEL)阳性细胞率、细胞凋亡率、细胞Bcl-2蛋白均显著降低,TLR9和MyD88蛋白、Bax、Bax/Bcl-2、Cleaved Caspase-3、Cleaved Caspase-9蛋白水平均明显增加(P<0.05);Control组、BRU-L、BRU-H组/BRU-H+pcDNA-NC呈持续递减/递减趋势(P<0.05);与BRU-H+pcDNA-NC组比较,BRU-H+pcDNA-TLR9组EDU阳性细胞率、TUNEL阳性细胞率、细胞凋亡率、细胞Bcl-2蛋白均显著升高,TLR9和MyD88蛋白、Bax、Bax/Bcl-2、Cleaved Caspase-3、Cleaved Caspase-9蛋白水平均明显降低(P<0.05)。与Control组比较,BRU-L、BRU-H组、BRU-H+pcDNA-NC组细胞JC-1水平和ATP含量显著降低,而ROC含量、mitotracker染色阳性细胞水平显著增加(P<0.05);与BRU-L组比较,BRU-H组、BRU-H+pcDNANC组JC-1水平和ATP含量进一步降低,而ROC含量、mitotracker染色阳性细胞水平进一步增加(P<0.05);与BRU-H+pcDNA-NC组比较,BRU-H+pcDNA-TLR9组细胞JC-1水平和ATP含量增加,而ROC含量、mitotracker染色阳性细胞水平降低(P<0.05)。结论鸦胆子苦醇可通过调控TLR9-MyD88信号通路制Hela细胞增殖。

Objective To investigate the molecular mechanism of Brusatol(BRU)regulating apoptosis of Hela cells through TLR9-MyD88 signaling pathway.Methods Hela cells preserved in our laboratory were treated with Brucea javanica at different concentrations(0,5.0,10.0,20.0,40.0,80.0 nmol·L^(-1)).Hela cells were divided into Control group(normal cultured Hela cells),BRU-L group(treated with 10.0 nmol·L^(-1)Brucea javanica)and BRU group-H(treated with 20.0 nmol·L^(-1)Brucea javanica)Cells were treated with nmol·L^(-1)of Brucea javanica),BRU+pcDNA-NC group(transfected with pcDNA-NC+20.0 nmol·L^(-1)of Brucea javanica),BRU-H+pcDNA-TLR9 group(transfected with pcDNA-TLR9+20.0 nmol·L^(-1)of Brucea javanica).Cell proliferation was detected by CCK-8 and EdU methods.Apoptosis was detected by TUNNEL staining and flow cytometry.The protein expression levels of TLR9,MyD88,Bax,Bcl-2,Cleaved Caspase-3 and Cleaved Caspase-9 were detected by Western blot.Cell apoptosis and mitochondrial membrane potential detection kit(JC-1)were detected by flow cytometry,and the contents of adenosine triphosphate(ATP)and reactive oxygen species(ROS)were detected by ELISA.Results Compared with 0 nmol·L^(-1)group,the survival rate and IC50 value of 10 nmol·L^(-1)group were significantly decreased(P<0.05).After stimulation of BRU with different concentrations,the proliferation ability of cells was significantly decreased in a dose-dependent manner(P<0.05).Compared with control group,the 5-ethynyl-2′-deoxyuracil(EDU)positive cell rate,TUNEL positive cell rate,apoptosis rate and Bcl-2 protein of cells in BRU-L,BRU-H and pcDNA-NC groups were significantly decreased.The protein levels of TLR9 and MyD88,Bax,Bax/Bcl-2,Cleaved Caspase-3 and Cleaved Caspase-9 were significantly increased(P<0.05).In control group,BRU-L,BRU-H group/BRU-H+pcDNA-NC,there was a continuous decreasing trend(P<0.05).Compared with the BRU-H+pcDNA-NC group,the EDU positive cell rate,TUNEL positive cell rate,apoptosis rate and Bcl-2 protein in the BRU-H+pcDNA-TLR9 group were significantly increased.The protein levels of TLR9 and MyD88,Bax,Bax/Bcl-2,Cleaved Caspase-3 and Cleaved Caspase-9 were significantly decreased(P<0.05).Compared with Control group,JC-1 level and ATP content in BRU-L,BRU-H and BRU-H+pcDNA-NC groups were significantly decreased,while ROC content and mitotracker positive cell level were significantly increased(P<0.05).Compared with BRU-L group,JC-1 level and ATP content in BRU-H group and BRU-H+pcDNA-NC group were further decreased,while ROC content and mitotracker positive cell level were further increased(P<0.05).Compared with the BRU-H+pcDNA-NC group,the levels of JC-1 and ATP in the BRU-H+pcDNA-TLR9 group were increased,while the levels of ROC,mitotracker staining positive cells were decreased(P<0.05).Conclusion Brucea javanica can produce Hela cell proliferation by regulating TLR9-MyD88 signaling pathway.