β-diversity and microbial colonization
The results of β-diversity based on Euclidean distance showed that the intestinal microbiota changed at week 4 compared with week 0 with the three treatments. The gut microbial communities in FMT plus metformin group were significantly different (PERMANOVA, p < 0.05) between week 4 and week 0, while there was no significant difference in FMT alone nor in metformin group (Donor-recipient gut microbiota correlation rate. Subjects with effective engraftment: Percentage of subjects with ≥20% donor-associated microbiota.The colonization of donor-derived microbial species was analyzed and detected in post-FMT samples from all recipients in both FMT alone and FMT plus metformin groups, with percentage ranging from 3.1% to 73.7%.The results showed that 6 patients (66.7%) in the FMT group and 5 patients (62.5%) in the FMT plus metformin group achieved ≥20% donor-derived microbial species, which was considered as effective colonization. However, there was no significant difference in colonization rate between the two groups (p > 0.05) (