Cohabiting with ulcerative colitis patients decreases differences of gut microbiome between healthy individuals and the patients

<b>Background:</b> Ulcerative colitis (UC), which is characterized by chronic relapsing inflammation of the colon, results from a complex interaction of factors involving the host, environment, and microbiome. The present study aimed to investigate the gut microbial composition and metabolic variations in patients with UC and their spouses. <b>Materials and Methods:</b> Fecal samples were collected from 13 healthy spouses and couples with UC. 16S rRNA gene amplicon sequencing and metagenomics sequencing were used to analyze gut microbiota composition, pathways, gene expression, and enzyme activity, followed by the Kyoto Encyclopedia of Genes and Genomes. <b>Results:</b> We found that the microbiome diversity of couples with UC decreased, especially that of UC patients. Bacterial composition, such as Firmicutes, was altered between UC patients and healthy controls, but was not significantly different between UC patients and their spouses. This has also been observed in pathways, such as metabolism, genetic information processing, organismal systems, and human diseases. However, the genes and enzymes of spouses with UC were not significantly different from those of healthy individuals. Furthermore, the presence of <i>Faecalibacterium</i> correlated with oxidative phosphorylation, starch and sucrose metabolism, amino sugar and nucleotide sugar metabolism, and the bacterial secretion system, showed a marked decline in the UC group compared with their spouses, but did not vary between healthy couples. <b>Conclusion</b>: Our study revealed that cohabitation with UC patients decreased differences in the gut microbiome between healthy individuals and patients. Not only was the composition and diversity of the microbiota diminished, but active pathways also showed some decline. Furthermore, Firmicutes, <i>Faecalibacterium,</i> and the four related pathways may be associated with the pathological state of the host rather than with human behavior.

**背景：** 溃疡性结肠炎（Ulcerative colitis, UC）是以结肠慢性复发性炎症为特征的疾病，其发病机制涉及宿主、环境与微生物组之间的复杂相互作用。本研究旨在探究溃疡性结肠炎患者及其配偶的肠道菌群组成与代谢特征差异。**材料与方法：** 本研究从13对溃疡性结肠炎患者与其健康配偶中采集粪便样本。采用16S rRNA基因扩增子测序与宏基因组测序技术，分析肠道菌群组成、代谢通路、基因表达及酶活性，并依托京都基因与基因组百科全书（Kyoto Encyclopedia of Genes and Genomes, KEGG）进行后续注释分析。**结果：** 研究发现，溃疡性结肠炎患者及其配偶组成的夫妻对的菌群多样性出现下降，其中溃疡性结肠炎患者的菌群多样性降低尤为显著。溃疡性结肠炎患者与健康对照的菌群组成（如厚壁菌门）存在显著差异，但溃疡性结肠炎患者与其健康配偶之间的菌群组成并无统计学意义上的显著差异。代谢通路层面也观察到类似的变化趋势，包括代谢、遗传信息加工、生物系统及人类疾病相关通路。不过，溃疡性结肠炎患者的健康配偶的菌群相关基因与酶活性与健康个体并无显著差异。此外，粪杆菌属（Faecalibacterium）的相对丰度与氧化磷酸化、淀粉与蔗糖代谢、氨基糖与核苷酸糖代谢以及细菌分泌系统密切相关，该菌属在溃疡性结肠炎组中的丰度较其健康配偶组显著降低，但在健康夫妻队列中并无明显波动。**结论：** 本研究揭示，与溃疡性结肠炎患者共同生活可缩小健康个体与患者之间的肠道菌群差异。不仅菌群的组成与多样性发生显著衰减，其活跃代谢通路也呈现一定程度的下调。此外，厚壁菌门、粪杆菌属以及上述四条相关代谢通路或与宿主的病理状态直接相关，而非受人类行为模式影响。