基于“肺-肠”微生态-代谢-免疫轴的川贝母活性物质组治疗哮喘的作用机制研究

The clinical effect of Fritillariae Cirrhosae Bulbus (FCB) has been well documented, but its pharmacological chemome and action mechanism is still unclear. In view of the “lung-intestinal” axis clues found in asthmatic patients and the theory of “the lung and intestine being interior-exteriorly related” in traditional Chinese medicine, we found that the FCB can ameliorate airway inflammation of allergic asthma through promoting the production of intestinal short chain fatty acids (SCFAs) and further activation of specific receptor GPR41. Therefore, this project is aim to investigate the mechanism of bioactive chemome of FCB (BCF) based on “lung-intestine” microbial-metabolite-immune axis in asthma. Firstly, chemomes of FCB with different structure were prepared and standardized for screening BCF using ovalbumin (OVA) challenged asthmatic mice, which were also validated using house dust mite extract (HDM) challenged asthmatic mice. Secondly, the microbiota and metabolites that BCF targeted were screened by metagenomics and metabolomics tools. Their functional correlation network was also constructed and validated by in vivo and in vitro test. Finally, based on these clues, we intend to unravel the mechanism of BCF in intervening the lung-gut microbiota, increasing the circulating levels of SCFAs, which act to impair the capacity of dendritic cell (DC) to instigate CD4+T cell-mediated immune response depends on G protein-coupled receptor 41 (GPR41). We expect that this study will not only contribute to unravel the pharmacological chemome and mechanism of FCB in treatment of asthma, but also supply new ideas and methods for the development of new drugs with improved prognosis for asthma.

川贝母治疗哮喘的临床疗效肯定，但其药效物质基础和作用机制尚不明确。针对已发现的哮喘病中“肺-肠”轴线索，在中医药“肺与大肠相表里”理论的启示下，前期研究发现川贝母可促进肠道短链脂肪酸（SCFAs）的生成，激活特异性受体GPR41，缓解哮喘模型小鼠气道炎症的症状。因此，本项目提出基于“肺-肠”微生态-代谢-免疫轴阐明川贝母活性物质组治疗哮喘的作用机制：①制备质量可控的川贝母各结构物质组，基于整体动物的多指标活性评价体系发现其活性物质组；②基于宏基因组学和代谢组学方法发现活性物质组作用的疾病相关菌群及功能代谢组，构建功能相关性网络，并验证；③基于以上线索，解析“SCFAs-GPR41”通过DC和CD4+T细胞调控哮喘异常免疫应答的机制，探讨川贝母活性物质组治疗哮喘的作用机理。最终揭示川贝母治疗哮喘的药效物质基础和作用机理，为开发综合改善哮喘病预后的治疗策略提供新的线索。

本项目基于“肺-肠”微生态-代谢-免疫轴系统研究了川贝母活性物质组治疗哮喘的作用机制：①开发了川贝母各组分的制备工艺，基于整体动物的多指标活性评价体系评价了各组物质的活性；②基于靶向代谢组学方法发现了川贝母活性物质所作用的疾病相关代谢组，并通过伪无菌鼠模型验证了其发挥作用是依赖于对肠道微生物的调控；③最后，通过探索菌群代谢物SCFAs-GPR41轴在DC细胞和CD4+T细胞调控哮喘异常免疫应答中的作用，解析了川贝母活性物质组治疗哮喘的作用机理。研究结果以论文形式发表，发表SCI论文14篇，申请专利1项，培养了2名博士和4名硕士。通过本项目的研究我们发现川贝母的主要活性成分不仅仅是传统上认为的生物碱，甾体皂苷和多糖组分亦是其活性物质；另外，本研究为阐明“肺与大肠相表里”理论的科学内涵提供了证据，为开发改善哮喘病预后的治疗策略提供新的线索。