Gut microbiome in UC couples. Variations in the gut microbiome from Ulcerative Colitis patients are not as great as expected

Ulcerative colitis (UC), characterized as chronic relapsing inflammation of the colon, results from a complex interaction of factors involving the host, environment, and microbiome. The present study aimed at investigating gut microbial composition and metabolic variations of UC patients and their spouses. Fecal samples were collected from 13 pairs of healthy spouses and UC couples. 16S rRNA gene amplicon sequencing and metagenomics sequencing were used to analyze gut microbiota composition, pathways, gene expression, and enzyme activity followed by Kyoto Encyclopedia of Genes and Genomes. We found the microbiome diversity of UC couples decreased, especially that of UC patients. Bacteria composition, such as Firmicutes, were altered between UC and healthy control, but were not significantly different between UC and their spouses. This was also observed in pathways such as metabolism, genetic information processing, organismal systems, and human diseases. However, genes and enzymes of UC spouses were not significantly different when compared with healthy individuals. Further, the presence of Faecalibacterium correlated with oxidative phosphorylation, starch and sucrose metabolism, amino sugar and nucleotide sugar metabolism, and bacterial secretion system, showed a marked decline in the UC group compared with their spouses, but not varied between healthy couples. In conclusion, our study revealed that cohabitation with UC patients made differences of gut microbiome between healthy individuals and the patients decrease. Not only was the composition and diversity of microbiota diminished, but also active pathways showed some decline. Furthermore, part of Firmicutes, Faecalibacterium, and the four related pathways may be associated with the pathological state of the host rather than with human behavior.