The change and recovery of human skin barrier functions after ultraviolet light irradiation.

Abstract

The changing patterns of in vivo human skin barrier functions after irradiation with a single middle-wavelength UV light (UV-B) were determined with respect to transepidermal water loss (TWL) and skin surface lipid values. A significant increase of the TWL value was found 1 wk after UV-B exposure at the site irradiated with twice the minimal erythemal dose (MED). Cholesterol value in skin surface lipid was raised significantly 2 or 3 wk after UV-B exposure at the 2 MED site. Total lipid and squalene values showed no significant differences. The TWL value recovered after 3 wk to the initial control level at all UV-B energy doses. Similar tendencies were observed in the cases of total lipid, squalene and cholesterol values. The increase of energy dose was parallel to the increase of the TWL value, i.e. lowering of the barrier efficacy of the corneal layer.