Background: Th2 cells are overexpressed in the skin and serum of atopic dermatitis (AD) patients. Previously, we found that dehydroepiandrosterone (DHEA) decreased eosinophil infiltration in asthmatic mice through the suppression of Th2-associated cytokines. Therefore, we hypothesized that DHEA might improve the symptoms of AD syndrome.
Objective: In this study, we evaluated the symptom improvement and anti-inflammatory response that result from the modulation of immunity by DHEA modulated in AD-like mice.
Methods: Female BALB/c mice were sensitized and challenged with 1-chloro-2,4-dinitrobenzene. On days 14-29 after sensitization, mice were treated with cutaneous (skin smear) or oral administration of DHEA. In addition, human keratinocyte (HaCat) cells were used to evaluate the effect of DHEA on the in vitro production of proinflammatory cytokines and chemokines.
Results: Both cutaneous and oral DHEA were able to decrease ear swelling and skin inflammation in AD-like mice. DHEA also attenuated eosinophil and mast cell infiltration into ear and skin tissue. Additionally, Th2-associated cytokines were inhibited in splenocyte culture, and suppressed the levels of IgE and interleukin 4 in serum. Oral and cutaneous administration of DHEA reduced the inflammatory response, as evidenced by AD-like skin lesions, in a similar manner. DHEA significantly reduced inflammatory cytokines and chemokines through the nuclear factor-κB and mitogen-activated protein kinases pathways in tumor necrosis factor-α activated HaCat cells.
Conclusion: DHEA ameliorates AD-like mouse skin inflammation and reduces eosinophil and mast cell infiltration by reducing the production of Th2-associated cytokines and chemokines.
Keywords: Atopic dermatitis; Chemokine; Cytokine; Dehydroepiandrosterone; Eosinophil.
Copyright © 2013 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.