Abstract
This study investigates the safety and underlying mechanisms of fecal microbiota transplantation (FMT) in treating radiation enteritis (RE). A rat model of RE was established with six groups: NC, RT, H-FMT, modified FMT (M-FMT), L-FMT, and BTAC. The therapeutic effects of FMT were assessed using the Disease Activity Index (DAI), histological analysis, and biochemical tests, including ink-propelling, xylitol exclusion, and enzyme-linked immunosorbent assay (ELISA). Gut microbiota alterations and fecal metabolism were analyzed via 16S rDNA sequencing and targeted metabolomics. The results demonstrated that FMT, particularly in the M-FMT group, effectively alleviated RE by reducing DAI scores, histological damage, and inflammatory markers while enhancing enzyme activity, superoxide dismutase (SOD) levels, and intestinal absorption. FMT also modulated gut microbiota composition, increasing beneficial species, such as Blautia wexlerae and Romboutsia timonensis while decreasing Enterococcus ratti. Metabolomics analysis revealed that FMT influenced niacin, nicotinamide, and starch metabolism, with notable changes in pantothenic acid and fatty acid levels. Spearman correlation analysis further indicated that these microbial shifts were associated with improved metabolic profiles. Overall, FMT mitigates RE by regulating gut microbiota and metabolites, with pantothenic acid and fatty acids emerging as potential therapeutic targets. Further research is needed to explore the underlying mechanisms in greater detail.