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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, OBJECTIVE, METHODS, RESULTS. Meshes: Animals, Cytokines, Dermatitis, Atopic, Dexamethasone, Disease Models, Animal, Keratinocytes, Male, Mice, Inbred BALB C, Tacrolimus, Tumor Necrosis Factor-alpha.
user
Does dexamethasone but not tacrolimus suppress TNF-α-induced thymic stromal lymphopoietin expression in lesional keratinocytes of atopic dermatitis model? Context: Thymic stromal lymphopoietin (TSLP) initiates the Th2-type allergic inflammation, and is thought to play an important role in the pathogenesis of atopic dermatitis (AD). TNF-α is a key cytokine which is involved in the pathophysiology of various inflammatory diseases, and the expression level is elevated in the sera and skin of patients with AD. In addition, TNF-α has been reported to induce TSLP expression in epidermal keratinocytes. Topical glucocorticoids and calcineurin inhibitors are safe and effective agents for AD, but the effects of these agents on TNF-α-induced TSLP expression are not fully understood. To investigate whether the glucocorticosteroid dexamethasone and the calcineurin inhibitor tacrolimus could affect TSLP expression induced by TNF-α in lesional keratinocytes of AD. The effects of topical dexamethasone and tacrolimus on TSLP expression were evaluated in an AD mouse model induced by repeated 2,4,6-trinitro-1-chlorobenzene application. Co-immunostaining for TSLP and TNF-α was performed using skin samples from AD patients and the mouse model. Normal human epidermal keratinocytes (NHEKs) were cultured with dexamethasone or tacrolimus in the presence of TNF-α to analyze TSLP expression. Topical application of dexamethasone but not tacrolimus repressed TSLP expression in the mouse model. TSLP and TNF-α showed similar distribution pattern in epidermal keratinocytes of AD lesions and the mouse model. TSLP expression was induced by TNF-α via NF-κB in a dose-dependent and an autocrine and/or paracrine manner in NHEKs, which was significantly suppressed by dexamethasone but not by tacrolimus. Similarly to TSLP expression, IL-6, TNF-α, IL-8, and IL-36γ expression induced by TNF-α were significantly suppressed by dexamethasone but not by tacrolimus in NHEKs.
assistant
Dexamethasone but not tacrolimus suppresses the TSLP expression induced by TNF-α in lesional keratinocytes of AD model. Our observations uncover the unreported functional difference between topical glucocorticosteroids and calcineurin inhibitors in cutaneous inflammatory diseases. Final Decision: yes