柯里拉京对血吸虫病肝纤维化过程中IL-13激活M2巨噬细胞胞内信号通路的干预机制研究

Recent studies have found that liver alternatively activated macrophages (M2 macrophages) play an important role in the schistosome egg granuloma induced liver fibrosis. Our previous National Natural Science Foundation study found corilagin can inhibit schistosome egg granuloma induced liver fibrosis by regulating IL-13 signal pathway. However, the mechanisms of how corilagin interfering with intracellular signal transduction pathways in alternatively activated macrophage remain further study. This topic is divided into two parts, cell and animal experiments. Mouse RAW264.7 macrophage cell line, mouse and human primary liver Kupffer cells were chosen as cell model. Stimulation by corilagin under under cell different conditions with or without IL-13 stimulation, lowered or raised key signaling molecules after IL-13 signaling pathway is activated the signaling pathways are examined, in order to make clear the target of corilagin to interact signal pathway in M2 macrophages. Further, in Balb / c mice, the mechanism will be validated. Through this research, we look forward to finding a clear mechanism of corilagin to interfere with alternative activation pathway of IL-13-induced liver macrophages, and making some contribution to the further control schistosomiasis liver fibrosis.

血吸虫病肝纤维化依然严重威胁我国公众健康。近年研究发现，肝脏替代途径活化的巨噬细胞（M2巨噬细胞）在血吸虫虫卵肉芽肿所致的肝纤维化过程中起重要作用。我们前一个国家自然基金研究发现柯里拉京能够通过调控IL-13抑制血吸虫虫卵肉芽肿所致的肝纤维化，然而，柯里拉京对肝脏替代途径活化的巨噬细胞胞内信号转导通路的干预作用机制尚待研究。本课题分为细胞和动物实验两个层面，拟以小鼠RAW264.7巨噬细胞株，小鼠和人原代肝脏枯否细胞分别为细胞模型，使用IL-13激活信号通路，采用小分子RNA干扰及慢病毒载体等技术，在信号通路上关键信号分子下调或上调的前提下采用柯里拉京干预，明确柯里拉京在细胞水平对巨噬细胞替代途径活化各靶点的作用及其机制。进而，在Balb/c小鼠体内进一步明确。通过此项研究，明确柯里拉京对IL-13诱导肝脏巨噬细胞替代活化途径的干预机制，为以其为靶点控制血吸虫病肝纤维化提供新策略。

项目按照计划进行，研究发现，柯里拉京通过干预 IL-13/STAT6信号通路及miR-21/smad7/ERK信号通路激活M2巨噬细胞而改善了小鼠血吸虫肝纤维的程度，可减轻血吸虫虫卵肉芽肿所致的肝脏纤维化病理学损害，降低肝脏羟脯氨酸含量，减少促纤维化型细胞因子IL-13的分泌，下调脾细胞GATA3 mRNA及肝组织Arg1 mRNA的转录水平，抑制肝脏精氨酸酶1的生成，减少肝组织中I型和III型胶原的生成，减少JAK-1的合成，抑制血吸虫病肝纤维化的形成与进展。同时，对出除柯里拉京外的另外同类植物中具备类似护肝作用的几种化学活性物质进行筛选，发现除柯里拉京外，还有绿原酸具备抗血吸虫肝纤维化的作用，因此在进一步的实验中和柯里拉京了进行比照性研究，发现绿原酸也可以通过影响miR-21/smad7/ERK信号通路而减轻小鼠血吸虫肝纤维化的程度。总之，本研究发现柯里拉京可以通过干预IL-13/STAT6及miR-21/smad7/ERK信号通路而改善了小鼠血吸虫肝纤维的程度，为进一步研究打下了基础。本项目已经培养2名博士研究生，并还有3名硕士研究生在读。本研究已发表SCI论文8篇，2篇SCI论文拟发表，并且还有1篇SCI论文在审稿中。