LAUSR

Purpose Many studies have investigated the association between intestinal barrier impairment and the onset of atopic dermatitis (AD). The gut microbiota is essential to maintain physiological homeostasis and immune regulation of host. Therefore, the objectives were to determine the effects of probiotics on the clinical symptoms, immune responses, and gut microbiota in AD patients. Methods 109 patients were randomly divided into 4 groups, including placebo group, oligosaccharides group, Bifidobacterium bifidum CCFM16 group, and Lactobacillus plantarum CCFM8610 group. At the end of the experiment, serological indicators, SCORAD, and DLQI indices were assessed. V3–V4 region of the 16S ribosomal RNA gene was sequenced to evaluate changes in the gut microbiota. Linear discriminant analysis (LDA) effect size was used to uncover microbial biomarkers and PICRUSt (Phylogenetic Investigation of Communities by Reconstruction of Unobserved States) was used to predict gene family abundances based on 16S information. Results The results demonstrated that CCFM8610 significantly decreased the SCORAD index, and increased the serum IL-10 levels. Supplement with CCFM8610 and CCFM16 significantly influenced the alpha diversity, increased the proportion of Bacteroidetes , and reduced the F/B ratio. CCFM8610 treatment downregulated the functional genes of gut microbiota involving Staphylococcus aureus infection and upregulated the steroid hormone biosynthesis. Conclusion The results indicated a positive correlation between decreased SCORAD index and CCFM8610 treatment, and that CCFM8610 regulated the immune responses in AD patients. CCFM8610 treatment influences the gut microbiota composition and functional changes. In conclusion, L. plantarum CCFM8610 exerts the strain-specific amelioration effects on patients with AD. Trial registration: ChiCTR1800015330 (Clinicaltrials.gov Identifier).