Involvement of Gut Microbiota in the Development of Psoriasis Vulgaris

Background Psoriasis is a common chronic recurrent dermatitis. Accumulating observations show gut microbiota dysbiosis in psoriasis. Objectives We intend to further investigate the relationship between intestinal microbiota and psoriasis development. Methods We first performed an epidemiological investigation on differences of gastrointestinal discomfort symptoms between psoriatic patients and general population. Then variation of gut microbiota in psoriatic patients (un)treated with Acitretin was analyzed by 16S rRNA sequencing. We last compared recovery status and vital cytokines of mouse psoriasiform models, which were transplanted with fecal microbiota from psoriatic patients or healthy controls. Results (1) 85.53% of psoriatic patients versus 58.08% of healthy controls presented with at least one gastrointestinal symptom. The prevalence of investigated symptoms (e.g. abdominal distension, constipation) were significantly higher in patients, compared with controls (p<0.05). Increased fart and constipation were significantly correlated with psoriasis (p<0.05, respectively). (2) The abundance of Ruminococcaceae family, Coprococcus_1 genus and Blautia genus were significantly decreased with psoriasis improvement, which had been demonstrated significantly increased in psoriasis. (3) Mice receiving psoriatic microflora transplantation showed significantly delayed recovery of psoriasiform dermatitis and less reduction of IL-17A, than those receiving healthy microflora or blank control (p<0.05 and p<0.01, respectively). Conclusions Multiple evidences we provided here demonstrate the involvement of gut microbiota in psoriasis development. The strategy based on gut microbiota is expected to be a promising supplementary for long-term management of psoriasis.