Acute stress enhances contact dermatitis by promoting nuclear factor-kappaB DNA-binding activity and interleukin-18 expression in mice.

Psychological stress adversely affects the immune system, and aggravates various skin diseases, such as psoriasis, alopecia areata and atopic dermatitis. However, the precise underlying mechanisms remain to be elucidated. The goal of this study was to use a murine restraint stress model to determine the mechanisms by which psychological stress modulates immune response in contact dermatitis. In the present study, mice were sensitized and challenged on the skin with 2,4-dinitrofluorobenzene. Acute restraint stress was administrated to healthy or sensitized mice before challenge, and nuclear factor (NF)-kappaB DNA-binding activation of nuclear protein and expression of interleukin (IL)-18 mRNA in murine spleen lymphocytes was detected. Chemical sympathectomy was performed using the neurotoxin 6-hydroxy-dopamine to determine the effect of the sympathetic nervous system. The experiment showed that restraint stress induced a series of changes which include increasing of NF-kappaB DNA-binding activity and IL-18 mRNA expression in spleen lymphocytes and enhancement of contact hypersensitivity response, and these changes may be mediated by the sympathetic nervous system. These findings provide new insights into the roles of the nervous system in the aggravation of skin diseases.