Potential Role of Probiotics in Ameliorating Psoriasis by Modulating Gut Microbiota in Imiquimod-Induced Psoriasis-Like Mice.

Psoriasis is an immune-mediated systemic disease that may be treated with probiotics. In this study, probiotic strains that could or could not decrease interleukin (IL)-17 levels were applied to imiquimod (IMQ)-induced psoriasis-like mice via oral administration. CCFM667, CCFM1078, CCFM1074, and CCFM1132 ameliorated psoriasis-like pathological characteristics and suppressed the release of IL-23/T helper cell 17 (Th17) axis-related inflammatory cytokines, whereas CCFM1148, CCFM1147, and CCFM1040 neither alleviated the pathological characteristics nor reduced the levels of inflammatory cytokines. All effective strains increased the contents of short-chain fatty acids, which were negatively correlated with the levels of inflammatory cytokines. By performing 16S rRNA gene sequencing, the diversity of gut microbiota in psoriasis-like mice was found to decrease, but all effective strains made some specific changes to the composition of gut microbiota compared to the ineffective strains. Furthermore, except for CCFM1078, all other effective strains decreased the abundance of the family Rikenellaceae, which was positively correlated with psoriasis-like pathological characteristics and was negatively correlated with propionate levels. These findings demonstrated effects of strain-specificity, and how probiotics ameliorated psoriasis and provide new possibilities for the treatment of psoriasis.