Observation on the efficacy and mechanism of Hirudoid in preventing psoriasis-like dermatitis in mice

Abstract

Objective To observe the preventive effect of Hirudoid (MPS) ointment on psoriasis-like dermatitis in mice and explore its mechanism. Methods 21 Balb/C mice were randomly divided into three groups: blank control group, positive control group (imiquimod group) and treatment group (imiquimod+ Hirudoid group). The blank control group was treated with imiquimod matrix. The positive control group was treated with 5% imiquimod cream to induce psoriatic dermatitis in mice′s back. The treatment group was treated with 5% imiquimod cream in the morning and Hirudoid cream in the afternoon. The changes of skin erythema, scales , infiltration severity and skin histopathology in the experimental area of mice back and serum levels of interleukin (IL)-17A and protein expression of tumor necrosis factor-α (TNF-α) in the three groups of mice were observed. Results The clinical and pathological findings of skin lesions in the positive control group showed that 5% imiquimod cream successfully induced psoriasis-like dermatitis in mice. The appearance and pathological feature of skin lesions in the blank control group were almost close to normal skin. The degree of erythema, infiltration and scales in the back of the treatment group was significantly less than that in the positive control group, and the degree of microscopic inflammation in the treatment group was also lighter than that in the positive control group; The serum levels of IL-17A and TNF-α in the treatment group and the blank control group were significantly lower than that of the positive control group, with statistically significant difference (P<0.05). Conclusions Hirudoid can significantly reduce imiquimod-induced psoriasis-like dermatitis by inhibiting the expression of IL-17A and TNF-α. Key words: Psoriasis; Glycosaminoglycans; Mice