异佛莱心苷抑制四氯化碳致小鼠肝纤维化的初步研究

Protective effect of isoviolanthin on hepatic fibrosis induced by carbon tetrachloride

关键词:  异佛莱心苷  肝纤维化  Smad2  丝氨酸/苏氨酸蛋白激酶B

Key words:  isoviolanthin  hepatic fibrosis  Smad2  protein kinase B

摘要:

目的探讨异佛莱心苷对四氯化碳(carbon tetrachloride, CCl4)所致小鼠肝纤维化的抑制作用。 方法将24只C57BL6J小鼠随机分为空白对照组、肝纤维化模型组、异佛莱心苷治疗组和水飞蓟素治疗组，每组6只。肝纤维化模型组、异佛莱心苷治疗组和水飞蓟素治疗组通过腹腔注射CCl4建立肝纤维化模型，每周3次，共12周。从第6周起，异佛莱心苷治疗组小鼠每日灌胃异佛莱心苷（10 mmol/L），水飞蓟素治疗组小鼠每日灌胃水飞蓟素100 mg/kg，连续给药6周。采集各组小鼠静脉血，血清检测丙氨酸氨基转移酶（alanine aminotransferase, ALT）和天冬氨酸氨基转移酶（aspartate aminotransferase, AST）；肝组织做HE染色、Masson染色和天狼星红染色；组织免疫荧光检测TGF-β1的表达；ELISA法检测各组血清中TGF-β1、IL-1β、IL-6和TNF-α含量；Western印迹法检测肝脏AKT/Smad2通路变化。 结果肝纤维化模型组血清ALT和AST较空白对照组显著升高(P<0.05)，异佛莱心苷治疗组和水飞蓟素治疗组小鼠血清ALT和AST均较肝纤维化模型组显著降低(P<0.05)，小鼠肝重和肝重/体重也较肝纤维化模型组显著降低(P<0.05)。两组小鼠肝组织病理学形态较肝纤维化模型组有一定程度的改善。组织免疫荧光显示肝纤维化模型组TGF-β1表达较空白对照组升高；异佛莱心苷和水飞蓟素治疗后肝脏TGF-β1表达降低。异佛莱心苷治疗组和水飞蓟素治疗组炎症指标（TGF-β1、IL-1β、IL-6和TNF-α）较肝纤维化模型组显著降低(P<0.05)。Western印迹法结果显示肝纤维化后p-Smad2、Smad2和p-AKT蛋白表达显著升高(P<0.05)，但异佛莱心苷治疗后肝脏组织中AKT/Smad2表达下降(P<0.05)，提示该通路异常激活被抑制。 结论异佛莱心苷对小鼠肝纤维化有抑制作用，其作用机制可能与抑制炎症反应和AKT/Smad2通路有关。

Abstract:

ObjectiveTo explore the protective effect of isoviolanthin on hepatic fibrosis induced by carbon tetrachloride(CCl4) in mice. MethodsC57BL6J mice were randomly divided into blank control group, model group, isoviolanthin group and silymarin group with 6 mice in each group. The mice in last tree groups were injected with CCl4 3 times every week for 12 weeks to establish the liver fibrosis model; and the isoviolanthin and silymarin groups were treated with isoviolanthin 10 mmol/(L·d)m or silymarin 100 mg/(kg·d) by gavage from 6th to 12th weeks, respectively. The serum ALT and AST levels, the body weight and liver weight were measured; HE, Masson and Sirius Red staining were preformed to evaluate the liver injury; the expression of TGF-β1 in liver tissue was detected by immunofluorescence; serum TGF-β1, IL-1β, IL-6 and TNF-α levels were detected by ELISA; the AKT/Smad2 pathway was measured by Western blotting. ResultsCompared with control group, the ALT and AST were increased in model group, which were markedly decreased by isoviolanthin and silymarin treatment(P<0.05). The liver weight and body weight were increased in model group, which were markedly decreased by isoviolanthin and silymarin treatment(P<0.05). HE, Masson and Sirius Red staining of liver tissue demonstrated that isoviolanthin and silymarin intervention improved the CCl4 induced liver injury. The expression of TGF-β1 in model group was higher than that in control group, while isoviolanthin and silymarin treatment decreased the TGF-β1 level. The levels of serum TGF-β1, IL-1β, IL-6 and TNF-α in the model group were significantly higher than those in control group(P<0.05), while those in isoviolanthin and silymarin groups had a significant decrease(P<0.05). There was a significant increasing in AKT/Smad2 expression in model, which was inhibited by isoviolanthin treatment. ConclusionIsoviolanthin has a protective effect on hepatic fibrosis in mice treated by CCl4, which may be associated with the suppression of AKT/Smad2 pathway.