Gut microbiota response to sucralose or rebaudioside A in rats under two dietary conditions

Abstract Research reported that sucralose induces metabolic derangements via gut microbiota modulation. However, rebaudioside A (reb A) exposure on gut microbiota has barely been evaluated. The aim of this study was to examine the gut microbiota response to sucralose or reb A in rats under two dietary conditions. Male Wistar rats (150–200 g) on normal diet (ND) or high-fat diet (HFD) were randomized to receive sucralose (SCL), reb A (REB), glucose (GLU, control), or sucrose (SUC). After eight weeks, fecal samples were analyzed by 16S ribosomal RNA gene sequencing. The diversity and the structure of the gut microbiota were not modified by NNS. In ND rats, SCL decreased phylum Firmicutes and increased Bacteroidetes and its genus Bacteroidia . At class level, in HFD rats, REB reduced Bacilli proportions. The genus Romboutsia was reduced with SCL and REB along ND. Lactobacillus increased with SCL and reduced with REB in HFD. After comparative analyses between the two types of diets, we observed that only HFD in combination with SCL increased Bacilli and diminished Bacteroidia abundances relative to ND. Exposure to NNS, at equivalent doses to the ADI, slightly induce modifications on gut microbiota in ND and HFD feeding rats, and the effects were more pronounced with sucralose ingestion combined with the HFD regimen. Further studies are needed to examine the potential mechanisms involved.