熊去氧胆酸下调Bax及半胱氨酸蛋白酶-3表达抑制骨髓间充质干细胞来源肝细胞凋亡  

UrsodeoxychoHc acid inhibits hepatocyte-like cell apoptosis by down-regulating the expressions of Bax and Caspase-3

作　　者：纪文娟[1] 曲强[1] 金晔[1] 赵磊[1] 何小东[1] 

机构地区：[1]中国医学科学院北京协和医学院北京协和医院基本外科,100730

出　　处：《中华医学杂志》2009年第42期2997-3001,共5页National Medical Journal of China

基　　金：国家自然科学基金（30871427）;教育部留学回国人员启动基金;北京协和医院科研重点项目（200305）

摘　　要：目的应用骨髓间充质干细胞诱导来源肝细胞研究熊去氧胆酸（UDCA）在肝细胞凋亡过程中的作用机制。方法体外诱导大鼠骨髓间充质干细胞分化为成熟肝细胞，应用去氧胆酸（DCA）诱导细胞凋亡（DCA组），UDCA干预（D＋U组），并设置非凋亡组（Cont组）和UDCA单独作用组（UDCA组）。凋亡细胞采用Hoechst染色和半胱氨酸蛋白酶（caspase-3）活性检测，半定量RT．PCR及Realtime RT—PCR检测p53及BaxmRNA表达，免疫组化方法检测Bax蛋白表达。结果与Cont组比较，DCA组肝细胞凋亡的数量及半胱氨酸蛋白酶3活性都明显增加（P〈0．05），而在D＋U组则被抑制（P〈0．05）。半定量RT—PCR及Realtime RT—PCR结果发现，p53及BaxmRNA的表达在DCA组中明显上调（P〈0．05），此上调可被UDCA抑制（P〈0．05）。DCA诱导的Bax（阳性细胞数量增加亦可被UDCA抑制。结论UDCA通过下调p53／Bax信号分子表达而抑制DCA诱导的肝细胞凋亡。Objective To investigate the mechanism of ursodeoxycholic acid（UDCA） in hepatocyte apoptosis using differentiated hepatocytes derived from bone marrow mesenchymal cells. Methods Rat bone marrow mesenchymal cell was induced into mature hepatocytes in vitro and then treated with PBS （ Cant）, deoxycholic acid （DCA）, DCA plus UDCA （U ＋ D） or UDCA alone （UDCA）. Cell apoptosis was detected by Hoechst staining and Caspase-3 activity measuremenL The mRNA expressions of p53 and Bax were measured by semi-quantitative RT-PCR and real-time RT-PCR. The Bax protein expression was detected by immunohistochemistry. Results In comparison with Cant, DCA obviously induced hepatocyte apoptosis as measured by an increased cell count and a higher Caspase-3 activity （P 〈 0. 05）. These increments could be inhibited by addition of UDCA. The expressions of p53 and Bax in hepatocytes were up-regulated by DCA. These up-expressions could also be inhibited by UDCA. The DCA-induced increased count of Bax-positive cells could be reduced by UDCA. Conclusion UDCA inhibits DCA-induced hepatoeyte apoptosis by downregulating the expression of p53/Bax signal molecule.

关 键 词：肝细胞 熊去氧胆酸 凋亡 半胱氨酸内肽酶类 

分 类 号：R686[医药卫生—骨科学]