Perspiration promotes the effect of sulphite on the shielding response of rodent skin

Abstract

Perspiration and environmental chemicals, such as air pollutants, are two of the complicating factors of skin disease. It has not been studied how perspiration affect the skin responding to air pollutants. We applied topically artificial eccrine perspiration, sulphite or both to the mouse skin for one and two weeks to examine the influence of both factors on the shielding ability of healthy skin. Morphological examination showed apparent thickening of the epidermal layer in the skin samples with combined treatment at 1 week, and in the sections applied with sulphite and combined treatment at 2 weeks without significant difference in the extent of epidermal hyperplasia between two groups. The outcomes of immunohistochemical (IHC) analysis showed elevated percentages of dermal fibroblasts expressing interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), tumor necrosis factor β (TNF-β) and cyclooxygenase-2 (Cox-2). Results of two-way repeated measured analysis of variance (two-way RMANOVA) showed that both perspiration and sulphite, but not the interaction between them, were significant factors affecting the expression of proinflammatory cytokines. The evidences indicated that perspiration induced cytokines expressions in the dermal fibroblasts and promoted the effect of sulphite on the shielding response of the skin by inducing epidermis hyperplasia.