【摘要】 目的:探讨双氢青蒿素(DHA)对大鼠肝纤维化损伤的缓解作用及对核因子E2相关因子2(Nrf2)/血红素加氧酶-1(HO-1)通路的影响。方法:取45只SD大鼠结扎胆管制备大鼠肝纤维化模型，造模成功的41只大鼠随机分为模型组(11只)、DHA低剂量组(10只)、DHA中剂量组(10只)、DHA高剂量组(10只)。DHA低、中、高剂量组大鼠分别给予5、15、25 mg/kg DHA灌胃，1次/d,连续14 d;假手术组、模型组大鼠灌胃等量无菌生理盐水。全自动生化分析仪检测血清中谷丙转氨酶(ALT)、谷草转氨酶(AST)和总胆红素(TBil)水平；试剂盒检测肝组织超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性和丙二醛(MDA)水平；HE染色观察大鼠肝组织病理学变化；Masson染色观察大鼠肝组织胶原沉积；Western Blot检测大鼠肝组织Nrf2/HO-1通路相关蛋白表达水平。结果:与模型组比较，DHA低剂量组、DHA中剂量组、DHA高剂量组大鼠血清ALT、AST、Tbil水平降低，肝组织SOD、GSH-Px活性升高，MDA水平降低，Nrf2、HO-1蛋白相对表达量升高(P<0.05);与DHA低剂量组比较，DHA中剂量组、DHA高剂量组大鼠血清ALT、AST、Tbil水平降低，肝组织SOD、GSH-Px活性升高，MDA水平降低，Nrf2、HO-1蛋白相对表达量升高(P<0.05);与DHA中剂量组比较，DHA高剂量组大鼠血清ALT、AST、Tbil水平降低，肝组织SOD、GSH-Px活性升高，MDA水平降低，Nrf2、HO-1蛋白相对表达量升高(P<0.05);HE染色及Masson染色结果显示，模型组大鼠肝细胞坏死，发生脂肪变性，排列紊乱，肝细胞间隙有炎性浸润，汇管区周围胶原纤维明显增生并向四周延伸，延伸至邻近肝小叶形成纤维间隔，多数纤维间隔完全包裹肝细胞团形成假小叶结构；DHA低、中、高剂量组大鼠较模型组大鼠肝组织损伤明显减轻，肝小叶结构均有不同程度恢复，较少肝细胞脂肪变性，炎性浸润不同程度减轻，汇管区周围胶原纤维增生明显减轻，纤维间隔变小，假小叶结构不明显，其中DHA高剂量组大鼠肝脏几乎未见胶原纤维组织增生及假小叶结构。结论:DHA对大鼠肝纤维化损伤具有缓解作用，可能与激活Nrf2/HO-1通路有关。更多还原

【Abstract】 Objective:To investigate the alleviating effect of dihydroartemisinin(DHA) on hepatic fibrosis injury in rats and its effect on nuclear factorerythroid-2 related factor 2(Nrf2)/heme oxygenase-1(HO-1)pathway.Methods:Forty-five SD rats were ligated with bile duct to prepare rat liver fibrosis model. Forty-one rats with successful modeling were randomly divided into model group(11 rats),low-dose DHA group(ten rats), medium-dose DHA group(ten rats)and high-dose DHA group(10 rats). The low, medium and high dose groups of DHA were given 5, 15 and 25 mg/kg DHA by gavage once a day for 14 consecutive days. The sham operation group and model group were given the same amount of sterile saline by gavage. The levels of alanine aminotransferase(ALT),aspartate aminotransferase(AST)and total bilirubin(Tbil)in serum were detected by automatic biochemical analyzer. The activities of superoxide dismutase(SOD), glutathione peroxidase(GSH-Px) and malondialdehyde(MDA) in liver tissue were detected by the kit. Pathological changes of liver tissue were observed by HE staining. Masson staining was used to observe collagen deposition in rat liver tissue. Western Blot was used to detect the expression levels of Nrf2/HO-1 pathway-related proteins in rat liver tissue. Results: Compared with the model group,the levels of ALT,AST,and Tbil in the serum of the DHA low dose group,DHA middle dose group,and DHA high dose group decreased,the activities of SOD and GSH-Px in liver tissue increased,the level of MDA decreased,and the relative expression of Nrf2 and HO-1 protein increased( P < 0. 05). Compared with low-dose DHA group,the levels of ALT,AST,and Tbil in serum were decreased,the activities of SOD and GSH-Px in liver tissue were increased,the level of MDA was decreased,and the relative expression of Nrf2 and HO-1 protein was increased in medium-dose DHA group and high-dose DHA group( P < 0. 05). Compared with medium-dose DHA group,the levels of ALT,AST and Tbil in serum of high-dose DHA group decreased,the activities of SOD and GSH-Px in liver tissue increased,the level of MDA decreased,and the relative expression of Nrf2and HO-1 protein increased( P < 0. 05). The results of HE staining and Masson staining showed that the hepatocytes in the model group were necrotic,fatty degeneration,and disordered arrangement. There was inflammatory infiltration in the hepatocyte space. Collagen fibers around the confluence area significantly proliferated and extended to the surrounding areas,extending to the adjacent hepatic lobules to form fibrous septa. Most fibrous septa completely wrapped the hepatocytes to form a pseudolobule structure. Compared with the model group,the liver tissue damage of rats in the low,medium,and high dose DHA groups was significantly reduced,and the liver lobular structure was restored to varying degrees. There was less steatosis of hepatocytes,and inflammatory infiltration was reduced to varying degrees. The collagen fiber proliferation around the confluence area was significantly reduced,and the fiber spacing became smaller,and the pseudo lobular structure was not obvious. There was almost no collagen fiber proliferation and pseudo lobular structure in the high dose DHA group. Conclusion: DHA can alleviate hepatic fibrosis injury in rats,which may be related to the activation of the Nrf2/HO-1 pathway.更多还原