基于肠道菌群及其代谢的芒硝干预大肠癌发生发展的机制研究

Mirabilite is the most common tradition Chinese medicine for the treatment of individuals in CRC because of its beneficial effects on gut. It was first recorded in “Ming Yi Bie Lu” in Nan Dynasty and showed that mirabilite could drive out tubercle in six hollow organs, soft or eliminate nodes or calculi in body. In the early stage, the research group discovered and confirmed the intervention effect of mirabilite in the occurrence and development of colorectal cancer by using spontaneous colorectal cancer transgenic animals. The inhibition rate against tumorigenesis was 75.6%, and the inhibition rate against tumor growth was 59.6%. Based on the study above, we plan to analysis baseline stool samples from control group, model group and the mirabilite groups, through an integration of 16S ribosomal RNA gene sequencing in this project, to evaluate the effect of mirabilite on intestinal microflora and related functional genes in intestinal cancer. The high-throughput metabolomics approach would also detect multiple samples. With the intervention of mirabilite, the metabolites of intestinal flora and host metabolites will be dynamically analyzed. To identify the biomarkers of intestinal tumorigenesis, we will evaluate the intervention effect of mirabilite on these biomarkers in the intestinal tumor model and explain the overall mechanism. On this basis, we will construct a complex network of gut microbiome-metabolite biomarkers and elucidate the direct targets and mechanisms of mirabilite intervention on intestinal cancer.

《本经集注》云芒硝 “逐六腑积聚，结固留癖”，在临床上配伍或单方用于治疗大肠癌等肠道疾病。课题组前期研究发现并确认了芒硝干预大肠癌发生发展的作用，其对肿瘤发生的抑制率为75.6%，对肿瘤生长的抑制率为59.6%。本课题基于大肠癌与肠道菌群的关系，进一步从组织病理学及生物化学角度研究芒硝对大肠癌发生发展的干预作用，并应用16S rRNA分析肠道菌群多样性，明确芒硝对自发性肠道腺瘤小鼠肠道菌群结构的调节作用及揭示其药效靶向菌群；进而采用代谢组学技术，表征芒硝对肠道腺瘤模型小鼠肠道菌群干预作用的代谢标记物，分析相关代谢通路；最后将肠道菌群多样性和生物标记物进行整合分析，构建代谢网络及动态关联，阐明芒硝干预肠道腺瘤发生发展的药效作用机制，为发现基于肠道菌群的预防大肠癌创新药物提供依据。

芒硝是临床用于治疗大肠癌的常用药物，但其作用机制仍不清楚。申请人分析芒硝对肠道肿瘤小鼠小肠内容物、盲肠内容物、结直肠内容物及粪便样本代谢轮廓及生物标记物的影响，并研究干预作用下肠道菌群丰度的改变，构建肿瘤因子-代谢通路-药效作用肠道菌群生物学网络，阐释芒硝对肠道肿瘤的干预作用及机制。. 首先，以临床生化指标及组织病理学手段对肠道肿瘤模型进行评价，利用代谢组学技术对模型组小肠内容物、盲肠内容物、结直肠内容物及粪便样本进行代谢组学分析，通过多数据库拟合构建肠道肿瘤因子-核心代谢通路-核心肠道菌群研究网络。在此基础上评价阐释芒硝的干预作用，研究芒硝对小肠内容物、盲肠内容物、结直肠内容物及粪便样本代谢轮廓及生物标记物的影响，构建芒硝药效肿瘤因子-核心药效代谢通路-核心药效肠道菌群研究体系。进一步利用高通量测序技术对肠道菌群多样性进行分析，研究芒硝直接作用的肠道微生物，并进行药效相关肠道菌群的靶向分析，确定与干预作用密切相关肠道菌群。最后，对核心药效生物标志物与药效相关肠道菌群进行整合分析，探究芒硝干预肠道肿瘤发生发展机制。. 结果表明，芒硝具有显著的干预肿瘤发生发展的作用。芒硝的作用位点在肠道菌群，虽然肠道肿瘤的发生是源于自身基因的缺失从而导致肿瘤的增殖，但芒硝对于肠道肿瘤的干预作用的靶点却在肠道菌群，即可以通过调控肠道肿瘤发生过程中的埃希氏杆菌，双歧杆菌，乳杆菌，罗氏菌，瘤胃球菌属，脱硫弧菌属及Anaerotruncus属微生物多样性的异常，对发生显著紊乱的胆汁酸代谢、核苷酸代谢及氨基酸代谢起到明显纠正作用，进而干预肿瘤的生长及增殖。. 该项研究结果对芒硝的临床的药用价值的提升及与芒硝作为传统药物抗大肠癌的机制研究具有指导意义。.