白屈菜红碱对肝纤维化小鼠TGF-β/Smads信号通路的影响

Effect of chelerythrine on TGF-β/Smads signaling pathway in mouse livers with hepatic fibrosis

目的:探讨白屈菜红碱对四氯化碳(CCl_4)诱导的肝纤维化损伤小鼠的保护作用及对转化生长因子β(TGF-β)/Smads信号通路的影响。方法:50只C57BL/6N小鼠随机分成正常对照组、模型组及白屈菜红碱低剂量(10 mg·kg^(-1)·d^(-1))、中剂量(20 mg·kg^(-1)·d^(-1))和高剂量(40 mg·kg^(-1)·d^(-1))3个剂量组,每组10只。采用腹腔注射CCl_4和橄榄油混合液8周诱导小鼠肝纤维化模型,白屈菜红碱组于第5周开始灌胃给药。第14周后处死小鼠,观察白屈菜红碱各剂量组干预后小鼠的肝指数,苏木精-伊红染色和苦味酸-酸性品红染色法观察小鼠肝组织的病理改变及肝纤维化的程度;采用分光光度计和酶标仪测定血清中天门冬氨酸氨基转移酶(AST)、丙氨酸氨基转移酶(ALT)、透明质酸(HA)和肝组织中羟脯氨酸(Hyp)的含量;RT-q PCR检测TGF-β1、Smad3、Smad4和Smad7的mRNA表达;Western blot检测TGF-β1、Smad4和Smad7的蛋白表达。结果:与正常对照组比较,模型组肝纤维化的病理改变明显,肝指数、AST、ALT、HA和Hyp均显著升高(P<0.05);TGF-β1、Smad3和Smad4的mRNA表达显著上调,Smad7的mRNA表达显著下调(P<0.05);TGF-β1和Smad4的蛋白表达显著上调,Smad7的蛋白表达显著下调(P<0.05);与模型组比较,白屈菜红碱不同剂量给药组均抑制上述指标的改变(P<0.05)。结论:白屈菜红碱能够抑制CCl_4诱导的小鼠肝纤维化,其机制可能与TGF-β/Smads信号通路有关。

AIM： To investigate the anti-hepatic fibrosis effect of chelerythrine on mice and the regulation of transforming growth factor-β（ TGF-β）/Smads signaling pathway. METHODS： C57 BL/6 N mice（ n = 50） were randomly divided into control group,model group and chelerythrine groups（ 10 mg·kg-1·d-1,20 mg·kg-1·d-1 and 40 mg·kg-1·d-1,ig）. The mouse model of hepatic fibrosis was established by intraperitoneal injection of carbon tetrachloride（ CCl4） in combination with the olive oil for 8 weeks. At the 5 th week,different doses of chelerythrine was used to treat hepatic fibrosis in the mice. At the 14 th week,hepatic index was detected. Histopathological changes and the degree of hepatic fibrosis were observed by hematoxylin-eosin staining and Van Gieson staining. The serum levels of alanine aminotransferase（ ALT）,aspartate aminotransferase（ AST） and hyaluronic acid（ HA）,and hepatic hydroxyproline（ Hyp） content were assayed by spectrophotometry and ELISA. The mRNA expression of TGF-β1,Smad3,Smad4 and Smad7 in the liver was detected by RT-q PCR,and the protein expression of TGF-β1,Smad4 and Smad7 was determined by Western blot.RESULTS： The degree of hepatic fibrosis changed markedly in model group compared with control group. The hepatic index,the serum levels of ALT and AST,and the contents of HA and Hyp were significantly increased（ P〈0. 05）. The mRNA expression of TGF-β1,Smad3 and Smad4 was significantly up-regulated,while the mRNA expression of Smad7 was significantly down-regulated（ P〈0. 05）. The protein expression of TGF-β1 and Smad4 was significantly up-regulated,while the protein expression of Smad7 was significantly down-regulated（ P〈0. 05）. Compared with model group,the changes of the above indexes in chelerythrine groups were inhibited. CONCLUSION： Chelerythrine protects the mouse liver from CCl4-induced fibrogenesis injury by regulating TGF-β/Smads signaling pathway.