基于代谢组学和宏基因组学技术的布-加综合征新型诊断标志物 及发病机制的研究

Budd-Chiari syndrome (B-CS) is a disease characterized by hepatic vein outflow obstruction, complicated by hepatic fibrosis and hepatocellular carcinoma. So far, little is known about the pathogenesis of B-CS. Our previous study found that B-CS urinary metabolites and intestinal flora presented characteristic changes. Thus, we proposed the hypothesis: B-CS can promote abnormal metabolism of liver, and induce characteristic changes of metabolic profile and intestinal microecology through the "liver-microbiology" axis, finally participating in B-CS pathology. In this study, we utilized liquid chromatography-mass spectrometry and metagenomics to illustrate intestinal microflora structure and functional gene changes as well as metabolic profile, and also conducted the correlation analysis and network pathway analysis between intestinal microflora and metabolic profile for B-CS. Furthermore, we constructed a non-invasive diagnostic model of B-CS based on microbial metagenomics, and identified the specific metabolic markers for B-CS disease. Meanwhile, the animal models of B-CS rats were constructed to identify the intestinal microflora and metabolic profile of B-CS rat by metagenomics and metabolomics techniques, to verify the pathogenesis of B-CS from the aspect of intestinal flora and metabolomics. This study will provide novel ideas for early warning monitoring, early prevention intervention and early diagnosis and treatment of B-CS disease.

布-加综合征(B-CS)是以肝静脉流出道阻塞为特征的疾病，可并发肝纤维化和肝癌，迄今对B-CS的发病机制仍知之甚少。我们前期研究发现，B-CS尿代谢物和肠道菌群呈特征性改变。基于此我们提出假说：B-CS可促发肝内外代谢异常，通过“肝脏-微生态”轴，机体代谢谱与肠道微生态发生特征性改变，进而参与B-CS病理演进。本课题采用液相色谱质谱联用和宏基因组学技术研究B-CS代谢谱、肠道菌群结构和功能基因变化，整合肠道菌群和机体代谢的关联分析及网络通路分析，从肠道菌群和机体代谢角度阐明B-CS演进机制，并基于肠道微生物信息构建B-CS的无创诊断模型，基于代谢组学筛选B-CS特异性的代谢标志物；同时，构建B-CS大鼠模型，利用宏基因组学和代谢组学技术鉴定大鼠B-CS的肠道菌群谱和代谢谱，验证肠道菌群和代谢参与B-CS的发病机制；本研究为B-CS早期预警监测、早期预防干预和早期诊治提供新思路。

布加综合征 (Budd-Chiari syndrome，B-CS) 是一种罕见且致命的血管性疾病，由原发性或继发性的肝静脉或肝后下腔静脉流出道梗阻所致。肠道微生态失调已被确定与布-加综合征的发生、发展密切相关，但肠道微生物组在布-加综合征发病机制中的作用仍不清楚。本团队进行了一项病例对照研究，通过宏基因组鸟枪法测序比较布-加综合征患者和健康家庭成员的粪便微生物组间的差异。为了阐明肠道微生态失调和布-加综合征之间的因果关系，我们在抗生素治疗过的小鼠模型中使用了粪便菌群移植 (FMT)。最后，我们通过 16S rDNA 扩增子测序、细胞因子分析和组织学程序测定了人和小鼠样本中的微生物组移位和免疫反应。布-加综合征患者肠道菌群表现出明显的微生态失调。机会性致病菌，特别是Campylobacter 和 Prevotella富集，而有益细菌，包括Lactobacillus 和 Saccharomyces在布-加综合征组中明显耗尽。在成功定植时，布-加综合征患者的肠道菌群引发了受体小鼠更显著的微生态失调。布-加综合征患者及其 FMT 小鼠表现出部分相同的肠道微生态失调和细胞因子失衡趋势。此外，布-加综合征粪便移植组表现出与肝脏和血管功能障碍相关的蛋白较高的表达。因此，免疫紊乱介导的肠道屏障破坏可能是布-加综合征发生所需的肠道菌群变化的基础。