Abstract
Probiotic candidate L. reuteri was screened out for in vivo experiments based on a relatively higher gastrointestinal tolerance and moderate adhesiveness. As results shown in in-vivo experiments, a significantly higher level of IL-12 at low-dose group was found both in females and males. Higher levels of T-lymphocytes were also observed in females compared to control group, however, males displayed a reduction expcept for CD8-positive cells in ileum. In comparison to the control group, the relative abundance of phylotypes in the phylum Bacteroidetes (genus of Bacteroides, Prevotella) and Firmicutes (genus of ClostridiumIV) exihibited a reserve shift between sexes after L. reuteri intervened. Meanwhile, the relative abundance of several taxa (Acetobacteroides, Lactobcaillus, bacillus) also differed markedly in sexes at low-dose group, together with microbiota diversity, as indicated by Shannon index.
Importance Sexual dimorphism has triggered researchers’ attention. However, the relationship between immune parameters and gut microbiota caused by Lactobacillus at different dosage are not fully elucidated. In present research, the possible probiotic role of L. reuteri DMSZ 8533 on immunomodulation and effect on fecal microbiota composition were investigated. Our findings demonstrate the importance of L. reuteri DMSZ 8533 as a potential probiotic strain with an immunomodulatory effect, which also alters the microflora composition depending on the sex of the host.