摘要
目的观察转化生长因子（TGF）β1、转化生长因子β受体（TβR）-Ⅰ、TpR-Ⅱ和胞内Smad 4信号通道蛋白以及转录因子激活剂蛋白-1（AP-1）家族中Jun蛋白质因子在大鼠非酒精性脂肪性肝病（NAFLD）中的表达，探讨NAFLD发生肝纤维化的可能机制。方法将18只大鼠分为对照组与模型组，每组9只。对照组喂饲普通饲料，模型组喂饲高脂饲料（88％标准普通饲料＋10％猪油＋2％胆固醇）造模。在20周处死所有大鼠，免疫组化法检测TGFβ1、Smad4的表达；RT—PCR检测肝组织TGFβ1、TβR—Ⅰ、TβR—Ⅱ的表达；Western印迹法测定磷酸化C—Jun蛋白的表达。结果成功建立NAFLD动物模型。免疫组化法检测结果显示，TGFβ1和Smad4在对照组大鼠肝实质细胞的胞质内均有少量表达。TGFβ1在模型组大鼠肝实质细胞胞质、肝血窦周围的表达明显增强，尤其在汇管区更为明显。Smad4在模型组大鼠肝实质细胞胞质表达亦明显增强，而在汇管区的表达更为明显。RT-PCR检测结果显示，模型组大鼠肝组织TGFβ1、TβRI、TBR-Ⅱ mRNA的A值分别为0．46±0．12、5．24±2．70和3．35±1．95，明显高于对照组（0．21±0．09、1．36±0．77和0．524-0．19，P值均〈0．01）。Western印迹检测显示，模型组磷酸化C—Jun蛋白表达同内参灰度值比为0．93±0．41，较对照组显著增高（0．32±0．25，P=0．001）。结论TGFβ1／Smad4信号通路可能参与了NAFLD进展为肝纤维化的过程。阻断TGFβ／Smad4信号传导通路，可开辟治疗NAFLD新的思路。
Objective To investigate the expression of transforming growth factor β1, transforming growth factor beta receptor （TβR） Ⅰ ,TβR Ⅱ ,Smad4 and C-Jun in rats with nonalcoholic fatty liver disease （NAFLD） and to find out the mechanisms of liver fibrosis in patients with NAFLD. Methods A total of 18 male SD rats were randomly divided into normal control group （n= 9） and model group （n=9）. The rats in control group were fed with normal diet, and those in model group were fed with fat rich diet （consisted of 10% lard oil ＋2% cholesterol）, All rats were sacrificed at the 20th week. The levels of TGFβ1, TβR Ⅰ and TβR Ⅱ mRNA were examined by RT-PCR. The expressions of TGFβⅠ and Smad4 in liver tissue were detected by immunohistochemistry. The expression of C-Jun protein was detected by Western blotting. Results The NAFLD model was successfully established. The immunohistochemistry examination revealed that TGFβ1 and Smad4 were expressed weekly in control group, but strongly expressed in model group. RT-PCR showed that Avaluesof TGFβ1, TβR Ⅰ and TβR Ⅱ mRNA were 0.46±0. 12,5. 24±2. 70 and 3. 35±1. 95, respectively, in model group, which were higher than those in control group （0. 21±0.09, 1.36± 0. 77 and 0. 52±0. 19, all P values〈0. 01）. The Western blotting results demonstrated that the expression of C-Jun protein in model group （0. 93±0. 41） was higher than that in control group （0.32± 0. 25, P=0. 001）. Conclusion TGFβ1/Smad4 signal pathway might be involved in the development of hepatic fibrosis in NAFLD. Blocking TGFβ1/Smad4 signal pathway will be helpful in treatment of NAFLD.
出处
《中华消化杂志》
CAS
CSCD
北大核心
2009年第5期317-321,共5页
Chinese Journal of Digestion
基金
上海市重点学科建设项目资助（Y0205）和上海市科学技术委员会基金资助（054119618）
