Liraglutide improved inflammation via mediating IL-23/Th-17 pathway in obese diabetic mice with psoriasiform skin

Objectives The purpose of this study was to investigate the effect of liraglutide on obesity diabetic mice with psoriasiform skin inflammation. Methods Wild-type mice and db/db mice were randomly divided into five groups (n = 6): including the control group which received Vaseline, the imiquimod (IMQ)-induction group and the liraglutide-treatment group. The advanced treatment with liraglutide (0.3 mg/kg/d) for 4 weeks before IMQ induced psoriatic skin inflammation in the db/db + IMQ + Lira group. Basic parameters of diabetes, PASI, histopathology of skin, the expression of IL-17A, IL-23, IL-22, and TNF-alpha in the skin of back were measured. Results After IMQ induction, the psoriatic skin inflammation and pathological changes in the db/db + IMQ group were more serious than those in the WT + IMQ group. The glucose metabolism and insulin resistance of in the db/db + IMQ + Lira group were significantly improved, Psoriasis Area and Severity Index (PASI) was significantly reduced, and the protein and mRNA expressions of IL-23, IL-17, IL-22, and TNF-alpha in the back skin tissues were decreased. Conclusions Liraglutide can improve psoriasis skin lesions of obese diabetic mice, and the mechanism may be related to the inhibition of the expression of IL-23, IL-17, IL-22, and TNF-alpha through the IL-23/Th-17 pathway.