北五味子粗多糖对四氯化碳致小鼠急性肝损伤的保护作用及其机制

目的：探讨北五味子粗多糖（SCP）对四氯化碳（CCl4）所致小鼠急性化学性肝损伤的保护作用，并初步揭示其作用机制。方法：将50只小鼠随机分为正常对照组、模型组、SCP低剂量组（50 mg/kg）、SCP高剂量组（100 mg/kg）和阳性药物组（联苯双酯，150 mg/kg）组，灌胃给药预处理15 d。末次给药1 h后，除正常对照组外其余4组采用10％CCl4 2.0 mL/kg一次性腹腔注射诱发小鼠急性肝损伤模型。6 h后摘眼球取血，断髓，取肝脏，计算各组小鼠肝指数，检测血清中谷氨酸氨基转移酶（ALT）和门冬氨酸氨基转移酶（AST）活性及总胆红素（TBIL）水平，检测肝组织中丙二醛（MDA）和还原型谷胱甘肽（GSH）水平及一氧化氮合酶（NOS）活性；HE染色观察肝脏病理学变化。结果：与正常对照组比较，模型组小鼠肝质量、肝指数、血清ALT和AST活性及TBIL水平、肝组织MDA水平及NOS活性均显著升高（P<0.01），肝组织GSH水平明显下降（P<0.01）。与模型组比较，SCP高剂量组小鼠肝脏质量和肝指数均明显降低（P<0.05），SCP低、高剂量组及阳性药物组小鼠血清ALT、AST活性和MDA水平均明显降低（P<0.05或P<0.01），肝组织GSH水平明显升高（P<0.05），SCP高剂量组小鼠血清TBIL水平和NOS活性均降低（P<0.05或P<0.01）。与阳性药物组比较，SCP低、高剂量组小鼠血清ALT和AST活性仍较高（P<0.05或P<0.01）。HE染色，模型组小鼠肝细胞体积增大，胞浆淡染，个别发生嗜酸性变性；SCP高剂量组肝细胞形态明显好转，肝细胞嗜酸性变性明显改善。结论：SCP对CCl4诱导的小鼠急性肝损伤具有明显的保护作用，其机制可能与抗氧化有关。

Protective effect of Schisandra polysaccharide on acute liver injury induced by CCl_4 in mice and its mechanism

Objective To explore the protective effect of Schisandra polysaccharide(SCP)on acute chemical liver injury induced by carbon tetrachloride(CCl4)in mice and to reveal its mechanism.Methods 50 mice were randomly divided into normal control group,model group,low dose of SCP group(SCP,50mg·kg-1),high dose of SCP group(SCP,100mg·kg-1)and positive control group(bifendate,150mg·kg-1).All the mice were intragastrically administrated the corresponding agents respectively for 15d.1hafter the last administration, 10% CCl4(2.0mL·kg-1)was given to mice in all groups except control group in a single intraperitoneal injection to establish the acute liver injury mouse models.6hlater,the mice were sacrificed,and the liver index,alanine aminotransferase(ALT)and aspartate aminotransferase(AST)activities,total bilirubin(TBIL)level in serumwere detected,and the malondialdehyde(MDA)and glutathione(GSH)levels,and nitric oxide synthase(NOS) activity in liver tissue were tested.HE staining was performed for observing the pathological changes of the liver tissue.Results Compared with normal control group,the liver quality,liver index,ALT,AST levels and TBIL level in serum,the MDA level and NOS activity in liver tissue in model group were all increased significantly(P<0.01),and the GSH level in liver tissue was decreased(P<0.01).Compared with model group,the liver quality and liver index of the mice in high dose of SCP group were decreased(P<0.05);the ALT and AST activities in serum,and the MDA level in liver tissue in low dose of SCP,high dose of SCP and positive control groups were decreased significantly(P<0.05or P<0.01),while the GSH levels in liver tissue were increased(P<0.05);both the serum TBIL level and NOS activity in liver tissue in high dose of SCP group were reduced(P<0.05or P<0.01).Moreover,the HE staining results showed that the size of liver cells was increased and the cytoplasm was stained lightly,and eosinophilic degeneration could be also seen in some individual liver cells in model group.The morphological damage of liver cells and the eosinophilic degeneration were significantly improved in SCP group.Conclusion SCP has a significantly protective effect on CCl4-induced acute liver injury,which might be related to the anti-oxidation.