【摘要】 目的探讨以白细胞介素-1受体相关激酶-4(IRAK-4)为靶点,阻断内毒素胞内信号转导后对大鼠移植肝脏再灌注损伤(I/RI)的影响并探索肝移植时可行的RNA干扰(RNAi)治疗途径。方法两袖套法建立SD大鼠同种异体原位肝移植模型,随机分为冷缺血转染组、活体转染组及对照组。冷缺血转染组于冷缺血期经门静脉灌注转染携带IRAK-4-shRNA的质粒pSIIRAK-4;活体转染组在门静脉袖套吻合完成后,经门静脉分支注入pSIIRAK-4;对照组不予任何处理。按门静脉血流恢复后第0min、60min及180min分为三个亚组,RT-PCR及Western-blot测定肝组织的IRAK-4mRNA和蛋白表达水平;ELISA法测定受体血清TNF-α含量。采用TUNEL法检测肝细胞凋亡状态,透射电镜观察肝组织超微结构的病理形态学变化。结果再灌注后冷缺血转染组的IRAK-4表达明显低于同时点的活体转染组及对照组(P<0.01);同时,肝细胞凋亡指数、血清TNF-α含量及肝细胞、血窦内皮细胞损伤程度也明显低于后者。结论以IRAK-4为靶点的冷缺血期shRNAs转染途径能有效阻断内毒素胞内信号转导,进而减轻肝移植时的I/RI程度。更多还原

【Abstract】 Objective To explore the feasibility of interleukin 1 receptor associated kinase-4 (IRAK-4) as gene therapy target for liver ischemia/reperfusion injury (I/RI) and effective approach in vivo for short hairpin RNA (shRNA) interference used to gene therapy in liver graft hqappened. Methods Sprague-Dawley rats were randomly divided into three groups: the control group, the in vivo transfection group (IVT) and the cold ischemia transfection group (CIT). Experiments of orthotopic liver transplantation were performed by two-cuff method. CIT were perfused with IRAK-4-shRNA plasmid (pSIIRAK-4) during cold ischemia phase, IVT received the equivalent volumes (2 mL) of pSIIRAK-4 after portal vein inosculated, and the control group leaved without any treatment. At 0 min, 60 min and 180 min after reperfusion, the expression of IRAK-4 gene and protein level were determined by RT-PCR and Western blot. The serum TNF-α level was detected by ELISA. Liver histopathological changes and cell apoptosis were observed by electron microscope and TUNEL. Results After reperfusion, the expression of IRAK-4 were largely depressed in CIT than that of IVT and the control group(P<0.01), and furthermore, the serum TNF-α level, proportion of hepatocyte apoptosis and severity of hepatocyte injury were also lower than the latter. Conclusion These results indicate that depression IRAK-4 expression with IRAK-4-shRNA through portal vein perfusion during cold ischemia phase could effectively blunt graft hepatic I/RI.更多还原