连翘酯苷A对感染H9N2型禽流感小鼠Toll样受体4信号通路影响的研究

Effect of forsythoside A on Toll-like receptor 4 signal pathway in mice infected with H9N2 Avian influenza

【目的】探究连翘酯苷A对感染H9N2型禽流感病毒小鼠Toll样受体4信号通路的影响。【方法】采用滴鼻方法建立小鼠H9N2型禽流感病毒急性肺损伤模型,120只小鼠随机分为5组(对照组、模型组、低剂量组、中剂量组、高剂量组),连翘酯苷A治疗连续7 d,各组在3、5、7、14 d随机选3只小鼠,称量体质量后取肺组织进行肺水肿评估、细胞因子检测、病理切片制作及Toll样受体4相关蛋白变化检测。【结果】与对照组相比,模型组小鼠体质量显著下降出现肺水肿现象,加入连翘酯苷A治疗后体质量呈现上升趋势肺部症状减轻;显微镜观察,模型组小鼠肺部组织比对照组小鼠肺部组织损伤严重,加入连翘酯苷A治疗后有所缓解;模型组血清中细胞因子白介素6含量极显著高于对照组(P<0.01),加入连翘酯苷A治疗后,呈现下调趋势;与对照组相比,模型组髓样分化因子、核因子-κB及磷酸化核因子-κB蛋白表达量极显著高于对照组(P<0.01),中剂量组与高剂量组髓样分化因子、核因子-κB及磷酸化核因子-κB蛋白表达量极显著(P<0.01)低于模型组。【结论】连翘酯苷A可下调Toll样受体4信号通路相应蛋白减轻炎症因子释放。

【Objective】 To investigate the effect of forsythoside A on Toll-like receptor 4 signaling pathway in mice infected with H9 N2 subtype avian influenza virus. 【Methods】 A mouse model of H9 N2 subtype avian influenza virus acute lung injury was established by nasal drip. 120 mice were randomly divided into 5 groups(control group, model group, low-dose group, medium-dose group, and high-dose group). Forsythoside A was consecutive treated for 7 days. Three mice were randomly selected from each group at 3, 5, 7, 14 days, respectively, after weighing, the lung tissue was taken for pulmonary edema assessment, cytokine detection, pathological section preparation, and detection of Toll-like receptor 4 related protein changes. 【Result】 Compared with the control group, the mice in the model group showed a significant decrease in weight and pulmonary edema. After treatment with forsythiaside A, the body weight showed an upward trend and the pulmonary symptoms were reduced;microscopic observation showed that the lung tissues of the model group’s lung tissue was more damaged than that of the control group, the content of cytokine interleukin 6 in the model group was significantly higher than that in the control group(P<0.01). After the treatment with forsythoside A, it showed a downward trend;compared with the control group, the expression levels of myeloid differentiation factor 88, nuclear factor kappa-B and phosphorylated nuclear factor kappa-B protein in the model group were significantly higher than those in the control group(P<0.01). The expression of myeloid differentiation factor, nuclear factor kappa-B and phosphorylated nuclear factor kappa-B in the middle and high dose groups of forsythoside A was significantly lower than that in the model group(P<0.01). 【Conclusion】 Forsythoside A can down-regulate the corresponding protein of Toll-like receptor 4 signaling pathway and reduce the release of inflammatory factors.