目的 基于Janus激酶2/信号转导和转录激活因子3（Janus kinase 2/signal transducer and activator of transcription 3，JAK2/STAT3）通路介导的细胞因子表达研究流感相关脑病的发病机制，并进一步探讨麻杏石甘汤的干预作用。方法 以A型流感病毒（influenza A virus，IAV）滴鼻感染BALB/c小鼠为研究对象，设置对照组、模型组、奥司他韦组、抗病毒颗粒组和麻杏石甘汤组。给予相应药物治疗3、7 d后，计算小鼠脑指数；苏木素-伊红（HE）染色法观察肺组织、脑组织病理变化；qRT-PCR法检测脑组织中JAK2、STAT3、白细胞介素-1β（interleukin-1β，IL-1β）、IL-10和IL-4 mRNA表达；Western blotting法检测脑组织中JAK2、STAT3蛋白表达；免疫组化法检测脑组织中磷酸化STAT3（phosphorylated STAT3，p-STAT3）蛋白表达；ELISA法检测脑组织中IL-1β、IL-10和IL-4水平。结果 IAV肺部感染的小鼠脑指数增加（P＜0.05、0.01），肺组织及大脑皮质出现明显病理变化；脑组织中JAK2、STAT3、IL-1β基因和蛋白表达水平升高（P＜0.05、0.01），p-STAT3表达水平升高（P＜0.01），IL-10、IL-4基因表达水平降低（P＜0.01），IL-1β、IL-10和IL-4分泌水平失调（P＜0.05、0.01）。麻杏石甘汤能改善脑组织水肿及肺、脑组织病理变化，下调脑组织中JAK2、STAT3、IL-1β基因和蛋白表达水平（P＜0.05、0.01），下调p-STAT3表达水平（P＜0.01），上调IL-10、IL-4基因和蛋白的表达水平（P＜0.01）。结论 JAK2/STAT3通路介导的细胞因子失衡可能是流感相关脑病的分子机制之一，麻杏石甘汤作为有效的抗流感病毒中药复方，可通过调控JAK2/STAT3通路减轻IAV肺部感染小鼠的脑组织病理损伤。

Objective To study the pathogenesis of influenza associated encephalopathy based on cytokines expressions mediated by Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) pathway, and further explore intervention effect of Maxing Shigan Decoction (麻杏石甘汤). Methods Influenza A virus (IAV) intranasally infected BALB/c mice were used as research objects, control group, model group, oseltamivir group, antiviral granule group and Maxing Shigan Decoction group were set up. After 3 and 7 d of corresponding drug treatment, brain index of mice was calculated; Hematoxylin-eosin (HE) staining was used to observe the pathological changes of lung tissue and brain tissue; qRT-PCR method was used to detect JAK2, STAT3, interleukin-1β (IL-1β), IL-10 and IL-4 mRNA expressions; Western blotting was used to detect the protein expressions of JAK2 and STAT3 in brain tissue; Immunohistochemical method was used to detect phosphorylated STAT3 (p-STAT3) protein expression; IL-1β, IL-10 and IL-4 levels in brain tissue were detected by ELISA. Results Brain index of mice infected with IAV lung was increased (P < 0.05, 0.01), lung tissue and cerebral cortex showed obvious pathological changes; JAK2, STAT3, IL-1β gene and protein expressions in brain tissue were increased (P < 0.05, 0.01), p-STAT3 expression level was increased (P < 0.01), IL-10 and IL-4 gene expressions were decreased (P < 0.01), levels of IL-1β, IL-10 and IL-4 were unregulated (P < 0.05, 0.01). Maxing Shigan Decoction improved brain tissue edema and pathological changes in lung and brain tissue, down-regulated JAK2, STAT3, IL-1β gene and protein expression levels in brain tissue (P < 0.05, 0.01), down-regulated p-STAT3 expression level (P < 0.01), up-regulated IL-10, IL-4 gene and protein expression levels (P < 0.01). Conclusion Imbalance of cytokines mediated by JAK2/STAT3 pathway may be one of molecular mechanisms of influenza associated encephalopathy. As an effective anti-influenza virus Chinese medicine compound, Maxing Shigan Decoction can improve brain histopathological damage of mice with IAV lung infection by regulating JAK2/STAT3 pathway.

R285.5

国家自然科学基金资助项目（82074250）；国家自然科学基金资助项目（81774126）；国家自然科学基金资助项目（81973670）；湖南省自然科学基金资助项目（2020JJ4063）；长沙市杰出创新青年人才培养计划项目（2019-23）；湖南中医药大学中医药防治新型冠状病毒肺炎科研专项项目（2020XGXM03）；湖南省研究生优秀教学团队（基础医学研究生教学团队，[2019]370-118）；湖南中医药大学一流学科《基础医学》资助项目（NO：1）；湖南中医药大学研究生创新课题（2020CX01）；湖南中医药大学中西医结合一流学科开放基金资助项目（2020ZXYJH36，2020ZXYJH13，2020ZXYJH18）