摘要
目的探讨肝纤维化小鼠肝组织血管新生特点及其形成机制。方法 C57BL/6小鼠随机分为正常对照组与模型18h、4周、8周组,共4组。采用CCl4诱导小鼠肝纤维化模型。天狼猩红染色观察肝组织胶原沉积;免疫荧光检测肝组织vWF蛋白表达,分析微血管密度;扫描电镜及透射电镜观察肝窦内皮结构;Western blot法检测肝组织I型胶原、vWF、CD31、CD44、IV型胶原、VEGF、VEGFR2、ERK/p-ERK蛋白表达;RT-PCR检测肝组织HIF-1α、VEGFmRNA表达。结果与正常组相比,模型18h组上述指标无明显变化,模型4周和8周组除CD44蛋白表达明显减少外,vWF、CD31等蛋白表达均明显增加,以8周为著;扫描电镜及透射电镜可见肝窦内皮窗孔逐渐消失,内皮下连续性基底膜逐渐形成;与正常组相比,模型组肝组织HIF-1α/VEGF mRNA表达逐渐增加。结论肝窦毛细血管化是肝纤维化小鼠肝组织血管新生特点;缺氧诱导的HIF1α-VEGF信号通路基因和蛋白表达上调是血管新生的部分机制。
Objective To investigate the characteristic and mechanism of liver angiogenesis in a mouse model of liver fibrosis.Methods Forty-nine male C57BL/6 mice,were randomly divided into four groups： normal（n=10）,model 18 h（n=13）,model 4 wk（n=13）,model 8 wk（n=13）.The model group was given 50% CCl4-olive oil subcutaneously injection.Sirius red staining was used to detection of hepatic collagen deposition;immunofluorescence assay for vWF was performed to analyze hepatic microvessel density;sinusoidal endothelial structure was observed by scanning electron microscope（SEM） and transmission electron microscope（TEM）;Western blot analysis were performed to assess the expression of collagen I,vWF,CD31,CD44,collagen IV,VEGF,VEGFR2,ERK and p-ERK protein levels;HIF-1α and VEGF mRNA was analyzed by real-time PCR.Results Compared with normal group,the hepatic collagen deposition and collagen I expression in model 18 h were not significantly changed;but increased gradually in 4 wk and 8 wk.The same trend was found in case of vWF and CD31.The expression of CD44 protein sowed no change in model 18 h when compared with normal group,while decreased in 4 wk and 8 wk;SEC lost their fenestrate and formed continuous basement membrane gradually;The expression of collagen IV protein also showed no change in 18 h,while increased gradually in 4 wk and 8 wk increased gradually;associated with CCl4 injection,HIF1α/VEGF mRNA was also increased in model groups.Conclusion Hepatic sinusoidal capillarization is the characteristic of liver angiogenesis in a mouse model of liver fibrosis;Hypoxia induced the increasing expression of HIF1α-VEGF signaling,contributing to the overall angiogenesis.
出处
《肝脏》
2011年第1期35-40,共6页
Chinese Hepatology
基金
国家自然科学基金(30901943)
上海市优秀学科带头人计划项目(08XD14041)
国家重点基础研究发展计划(973)项目(2006CB504801)
上海市教育委员会E-研究院建设计划项目(E0308)
上海市教委创新团队建设项目
