【摘要】 目的　研究 TGF-β1、Sm ad3、Smad7在血吸虫病肝纤维化家兔肝脏中的表达变化规律 ,为逆转血吸虫病肝纤维化寻找新的途径。方法　日本血吸虫尾蚴腹贴法制备家兔肝纤维化模型 (n=4 0 ) ,按诱导时间将动物随机分为 4、8、12、16周及正常对照共 5组 ,采用逆转录 -聚合酶链反应 (RT-PCR)检测肝组织中转化生长因子 TGF-β1m RNA表达水平 ,免疫组织化学检测肝组织中 、 型胶原的表达 ,且同时分别以 RT- PCR、Western blot检测原代分离肝星状细胞 (HSC)的 Sm ad3、Sm ad7m RNA和蛋白表达。结果　肝纤维化形成过程中 TGF- β1m RNA表达进行性增强 ,伴有肝组织 、 型胶原含量的明显增高 ,且分别与 、 型胶原呈显著正相关 (r1 =0 .5 36 ,P<0 .0 1;r2 =0 .5 4 4 ,P<0 .0 1) ; 、 型胶原表达在肝窦壁、中央静脉壁、Disse腔、虫卵肉芽肿内及其周围 ,呈弥漫状分布 ,伴有门管区胶原纤维隔形成和窦壁完整的基膜形成 ;与正常对照组相比 ,各期肝纤维化家兔 HSC中 Smad3m RNA表达增加 ,与 TGF- β1m RNA表达趋势基本一致。而 Sm ad7m RNA较正常对照组一过性升高 (P<0 .0 5 ) ,第 8～ 16周表达水平则持续下降 (P<0 .0 1)。 Smad蛋白表达与其m RNA改变基本一致。结论　 TGF- β1/ Smad信号通路参与了血吸虫病肝纤维化进程更多还原

【Abstract】 Objective To investigate changes in the expression of TGF-β1, Smad3 and Smad7 in liver of experimental hepatic fibrosis model of schistosomiasis japonica in rabbits. Methods Hepatic fibrosis models of rabbit were made by infection with the cercariae of Schistosoma japonicum (n=40).The rabbits were euthanatized at the 4th,8th,12th,16th weeks respectively after infection. The level of transforming growth factor-beta1 (TGF-β1) mRNA in hepatic tissues was examined by the reverse transcription polymerase chain reaction (RT-PCR). Type Ⅰ, Ⅲ collagens in liver were measured by the immunohistochemistry staining method. Meanwhile,the expressions of Smad3 and Smad7 in primary HSC,isolated from different period of rabbit liver fibrosis were examined by RT-PCR and Western blot. Results TGF-β1 mRNA gradually increased during hepatic fibrogenesis,and this trend was positively correlated to the increased production of type Ⅰ, Ⅲ collagens (r 1=0.536, P<0.01;r 2=0.544,P<0.01). Type Ⅰ, Ⅲ collagens were mainly expressed in walls of liver sinus and central veins,Disse cavity,and around granuloma of worm ova. Compared with the controls,the level of Smad3 mRNA in HSC of fibrotic rabbits increased significantly. The expression of Smad3 changed in similar way as TGF-β1 mRNA.Higher level of Smad7 mRNA was observed at four weeks later after the administration(P<0.05),but lower level was obtained from 8 weeks later until the end (P<0.01). The expressions of Smad3 and Smad7 proteins changed in similar way as their mRNA. Conclusion TGF-β1/Smad signaling is involved in the progression of hepatic fibrosis of schistosomiasis japonicum. Up-regulation of R-Smads proteins and down-regulation of Anti-Smads proteins may be a critical element in liver fibrogenesis.更多还原