茶多酚对NASH 大鼠肝脏组织VEGF 及氧化应激的影响

目的:茶多酚对NASH大鼠肝脏组织VEGF及氧化应激的影响。方法:雄性SD大鼠30只,随机分为3组,正常对照组、模型组、茶多酚治疗组。正常组普通饲料喂养,模型组喂高脂饮食,茶多酚治疗组在高脂饮食12周后茶多酚(150mg(/kg.d)灌胃治疗,16周末处死各组大鼠,留取肝脏组织,观察各组大鼠肝组织病理改变,测定其肝脏丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性以及血管内皮生长因子(VEGF)、Ⅰ、Ⅲ型胶原的表达。结果:模型组大鼠肝组织中SOD活性降低而MDA含量以及VEGF、Ⅰ、Ⅲ型胶原表达均明显高于正常组。茶多酚治疗可减轻肝纤维化程度,显著升高肝组织中SOD活性、降低MDA含量以及VEGF、Ⅰ、Ⅲ型胶原表达水平。结论:茶多酚可通过抑制肝纤维化组织VEGF表达,降低肝组织氧化应激水平而发挥抗肝纤维化作用。

Effects of Tea Polyphenol on VEGF and Oxidative Stress in Liver Tissues of Rats With Nonalcoholic Steatohepatitis

Objective: To investigate the effect of tea polyphenol on vascular endothelial growth factor(VEGF) and oxidative stress in liver tissues of rats with nonalcoholic steatohepatitis(NASH).Methods: Male SD rats were fed with normal diet(control group),high fat diet(model group),gavage fed with high fat diet(treatment group) and 12th weeks later was fed with tea polyphenol(150 mg/kg·d).The rats were sacrificed at the 16th week after the last gavage fed.The pathological changes of liver tissues,the content of malondialdehyde(MDA),the activity of superoxide dismutase(SOD),and the expression of VEGF,Ⅰand Ⅲ collagen were detected.Results: Compared with control group,SOD activity decreased significantly in model group rats.The MDA content and VEGF,Ⅰand Ⅲ collagen expression in model group rats were significantly higher than those in the normal group rats.Tea polyphenol could reduce the liver fibrosis level,MDA content,VEGF,Ⅰ,Ⅲ collagen expression.It also could increase the SOD activity.Conclusion: Tea polyphenols plays an important role in reducing hepatic fibrosis through inhibiting VEGF expression in liver fibrosis tissues and reducing the level of oxidative stress in liver tissues.