SINGLET OXYGEN IS AN EARLY INTERMEDIATE IN CYTOKINE-DEPENDENT ULTRAVIOLET-A INDUCTION OF INTERSTITIAL COLLAGENASE IN HUMAN DERMAL FIBROBLASTS IN-VITRO

Ultraviolet (UV) A irradiation of human dermal fibroblasts elicits an increase in specific mRNA amounts and bioactivities of the cytokines I L-1 alpha, IL-1 beta, and IL-6, These effects are enhanced in deuteriu m oxide-based medium and are diminished in the presence of non-toxic c oncentrations of sodium azide, Furthermore, generating singlet oxygen outside the cells by irradiation of rose bengal-coated resin particles with visible light (lambda > 450 nm) results in the induction of inte rstitial collagenase, IL-1 and IL-6, similar to the response observed with WA irradiation, These observations suggest that singlet oxygen is an early intermediate in the signaling pathway of IL-1 and IL-6 media ting UVA induction of interstitial collagenase (E.C. 3.4.24.7). Furthe rmore, singlet oxygen appears to initiate this complex UV response at the cell membrane. (C) 1997 Federation of European Biochemical Societi es.