Inhibitory effect of arazyme on the development of atopic dermatitis-like lesions in BALB/c and Nc/Nga mice

Arazyme is a metalloprotease released by Aranicola proteolyticus that was shown to inhibit cytokine release in HaCaT and endothelial cells. However, the regulatory effects of arazyme in atopic dermatitis remain to be fully understood. In the present study, the anti-inflammatory effects of arazyme in BALB/c and Nc/Nga mice induced with 2,4-dinitrochl-robenzene (DNCB) were investigated. BALB/c mice were sensitized with DNCB and were subsequently administered arazyme for 4 weeks either orally, dorsally or orally/dorsally. Arazyme administration significantly reduced epidermal thickening and infiltration of inflammatory cells into the dermis compared with the DNCB group. However, serum immunoglobulin E (IgE) levels were not altered by arazyme treatment. Additionally, the level of secretion of interleukins (IL)-4, -5 and -13 in the splenocytes of BALB/c mice was elevated following stimulation with concanavalin A, while the increase of IL-4 and IL-13 was inhibited by arazyme. Administration of arazyme (25 mg/kg in phosphate-buffered saline) to Nc/Nga mice that had been sensitized with DNCB for 6 weeks reduced the skin severity score compared with that in the DNCB group and inhibited the histological manifestations of atopic dermatitis-like skin lesions. In addition, the serum IgE levels were reduced in the arazyme-treated NC/Nga mice relative to the DNCB group. Collectively, these results indicated that arazyme attenuates the development of atopic dermatitis-like lesions via lowering the levels of IgE and inflammatory cytokines. The results of the present study will aid in the development of effective therapeutic strategies for the treatment of allergic diseases, including atopic dermatitis.