摘要
背景:CYP2E1是一种可被乙醇诱导的细胞色素P450酶。在非酒精性脂肪性肝病发病机制的"二次打击"学说中,CYP2E1介导的脂质过氧化发挥重要作用。目的:从改善氧化应激的角度探讨普洱茶(熟茶)茶粉、黑茶茶粉和六堡茶对非酒精性脂肪肝(NAFL)模型大鼠的辅助保护作用。方法:120只Wistar大鼠分为正常对照组、高脂模型组、降脂药物组以及低、中、高剂量(0.5、1.0、2.0 g/kg)普洱茶(熟茶)茶粉、黑茶茶粉、六堡茶组。以高脂饮食诱导NAFL模型,实验组予相应品种、剂量的茶汤灌胃35 d。处死大鼠,测定肝组织抗氧化指标,real time PCR检测肝细胞CYP2E1 mRNA表达,同时观察肝脏组织学表现。结果:适宜剂量的普洱茶(熟茶)茶粉和六堡茶能显著降低高脂模型大鼠的肝组织MDA含量,增高SOD、GSH-Px活性,抑制肝细胞CYP2E1 mRNA表达(P均<0.05)。高剂量六堡茶组肝脏组织学表现为轻度脂肪肝,高剂量普洱茶(熟茶)茶粉组和黑茶茶粉组表现为中度脂肪肝。结论:普洱茶(熟茶)茶粉和六堡茶对NAFL大鼠模型的肝脏抗氧化指标、CYP2E1基因表达和组织学表现具有积极作用,表明两者对NAFLD可发挥辅助保护作用,六堡茶的作用更为明显。
Background： CYP2E1 is an ethanol-inducible cytochrome P450 enzyme that plays an important role in the ＂two hits＂ hypothesis of nonalcoholic fatty liver disease by inducing lipid peroxidation. Aims： To investigate the auxiliary protective effect of Fermented Pu-erh Tea powder, Dark Tea powder and Liupu Tea on rats with experimental nonalcoholic fatty liver （NAFL） from the perspective of improving oxidative stress. Methods： One hundred and twenty Wistar rats were divided into normal control group, hyperlipidemia model group, hypolipidemic agent group and low, moderate and high dose （0.5, 1.0 and 2.0 g/kg） Fermented Pu-erh Tea powder, Dark Tea powder and Liupu Tea groups. NAFL was induced by high fat diet. Rats in experimental groups were administered intragastrically with different tea infusion for 35 days. All rats were sacrificed after 35 days feeding, several hepatic antioxidant indices were measured, the hepatocytic CYP2E1 mRNA expression was detected by real time PCR, and hepatic histopathologieal changes were also observed. Results： Eligible doses of Fermented Pu-erh Tea powder and Liupu Tea significantly decreased the concentration of MDA and expression of CYP2E1 mRNA, and increased the activities of SOD and GSH-Px in liver tissue of hyperlipidemic rats （ P all 〈 0.05）. Under microscopy, rats in high dose Liupu Tea group presented mild fatty liver and those in high dose Fermented Pu-erh Tea powder group and Dark Tea powder group presented moderate fatty liver. Conclusions： Fermented Pu-erh Tea powder and Liupu Tea have positive effects on antioxidant indices, CYP2E1 gene expression and histopathology of liver tissue in NAFL model rats, which denotes an auxiliary protective effect on NAFLD, and Liupu Tea is more effective than Fermented Pu-erh Tea powder.
出处
《胃肠病学》
2013年第7期411-415,共5页
Chinese Journal of Gastroenterology
基金
现代农业产业技术体系建设专项资金(CARS-23)
国家科技支撑计划(2007BAD58B04)
云南省生物资源开发创新项目(2007YNCXB-01-01)资助
