Jak/Stat信号通路在经典CCl_4大鼠肝纤维化模型中的动态变化及扶正化瘀方对其影响

Role of Jak /Stat pathway in CCl_4- induced rat liver fibrosis model and molecular action mechanism of Fuzheng Huayu recipe in treatment of liver fibrosis

目的探讨Jak/Stat信号通路在经典的CCl4大鼠肝纤维化模型中的动态变化及扶正化瘀方对其影响。方法复制经典的CCl4大鼠肝纤维化模型和肝纤维化扶正化瘀方干预模型,收集纤维化形成、逆转和干预过程中不同时间的血液和肝组织,观察血清指标、肝组织病理、α-SMA表达及肝组织Jak1、Stat3蛋白和mRNA表达变化。多组间比较采用单因素方差分析。结果 CCl4应用后模型组大鼠肝组织炎症及纤维化逐渐加重,α-SMA及Jak1、Stat3表达逐渐升高,8周时达高峰。8周后随着CCl4停用,大鼠肝组织炎症和纤维化逐渐好转,上述指标亦较前明显降低;扶正化瘀方干预组第4、6、8周时大鼠血清指标,肝组织炎症和纤维化程度、Jak1、Stat3表达均较模型组相同时间点明显降低。结论 Jak/Stat信号通路在肝纤维化发生和逆转中发挥重要作用,扶正化瘀方可通过阻断Jak/Stat通路及减少肝星状细胞活化发挥抗肝纤维化作用。

Objective To investigate the role of Jak/Stat pathway in the CCl4 - induced rat liver fibrosis model and the molecular action mechanism of Fuzheng Huayu recipe in the treatment of liver fibrosis. Methods Experimental rats were randomly divided into control group, CCl4 -induced liver fibrosis model group （model group）, and Fuzheng Huayu recipe group （FZHY group）. Blood and liver tissue samples were collected at different time points during fibrosis development, reversion, and intervention. Serum levels of alanine aminotransferase （ALT） and hyaluronic acid （HA） were determined by Olympus AU2700 automatic biochemical analyzer and radioimmunoassay, respectively. The degree of liver fibrosis was evaluated by the Ishak score system. The protein expression of alpha - smooth muscle actin （ a - SMA） was measured by immunohistochemistry. The mRNA and protein expression of Jakl and Stat3 was measured by RT - PCR and Western - Blot, respectively. Comparison between groups was made by one - way analysis of variance. Results During treatment with CCl4, the model group had increasing liver tissue inflammation and fibrosis, as well as elevated protein expression of a - SMA and mRNA and protein expression of Jakl and Star3, and these indices reached the peak levels at week 8 ; later, the rats showed improvements in liver tissue inflammation and fibrosis and significant decreases in the above indices after CCl4 were discontinued. At weeks 4, 6, and 8, the FZHY group had significantly decreased serum levels of ALT and HA, significantly reduced liver tissue inflammation and fibrosis, and significantly down - regulated mRNA and protein expression of Jakl and Stat3, as compared with the model group. Conclusion The Jak/Stat pathway plays an important role in the development and reversion of liver fibrosis. Fuzheng Huayu recipe can reduce liver fibrosis by blocking the Jak/Stat pathway and inhibiting activation of hepatic stellate cells.