Cultivated ginseng inhibits 2,4-dinitrochlorobenzene-induced atopic dermatitis-like skin lesions in NC/Nga mice and TNF-α/IFN-γ-induced TARC activation in HaCaT cells

Ginseng contains many bioactive constituents, including various ginsenosides that are believed to have anti-allergic, anti-oxidant, and immunostimulatory activities; however, its effects on atopic dermatitis (AD) remain unclear. In the current study, we hypothesized that cultivated ginseng (CG) would inhibit 2,4-dinitrochlorobenzene (DNCB)-induced AD-like skin lesions in NC/Nga mice by regulating the T helper (Th)1/Th2 balance. Also, CG inhibits TNF-α/IFN-γ-induced thymus- and activation-regulated chemokine (TARC) expression through nuclear factor-kappa B (NF-κB)-dependent signaling in HaCaT cells. CG ameliorated DNCB-induced dermatitis severity, serum levels of IgE and TARC, and mRNA expression of TARC, TNF-α, IFN-γ, IL-4, IL-5, and IL-13 in mice. Histopathological examination showed reduced thickness of the epidermis/dermis and dermal infiltration of inflammatory cells in the ears. Furthermore, CG suppressed the TNF-α/IFN-γ-induced mRNA expression of TARC in HaCaT cells. CG inhibited TNF-α/IFN-γ-induced NF-κB activation. These results suggest that CG inhibited the development of the AD-like skin symptoms by modulating Th1 and Th2 responses in the skin lesions in mice and TARC expression by suppressing TNF-α/IFN-γ-induced NF-κB activation in keratinocytes, and so may be a useful tool in the therapy of AD-like skin symptoms.