Solar-simulated irradiation evokes a persistent and biphasic IL-1alpha response.
Exposure of skin to solar-simulated irradiation generates a multitude of adaptive responses including cytokine transcription, synthesis and secretion. Interleukin-1 (IL-1) is one of the cytokines induced in epidermal cells in response to UV irradiation. It displays a broad range of mitogenic and inflammatory activities including fibroblast proliferation and T-cell activation. There are two forms, IL-1alpha and IL-1beta; and IL-1alpha is the predominant form secreted by epidermal keratinocytes. UV-induced modulations of IL-1alpha message levels have been extensively studied within the first 48 h after irradiation, but longer term changes and impact on IL-1alpha cellular protein levels are virtually unexplored. We now report that cells of keratinocyte origin (SCC 12F) respond to a single physiologic dose of solar-simulated irradiation with both early (8 h) and late (72 h) peaks of IL-1alpha mRNA induction. UV-stimulated IL-1alpha secretion is increased above sham-irradiated control secretion for at least 96 h after irradiation. Our study provides evidence that UV-induced adaptive cutaneous responses persist for at least several days, and suggests that different mechanisms may mediate the early vs. late inductions.
Nanjing Medical University, Department of Dermatology, Nanjing 210029, China.
Dan
D
Luo
Mina
M
Yaar
Angel
A
Tsai
Barbara A
BA
Gilchrest
D002294:Carcinoma, Squamous Cell; D045744:Cell Line, Tumor; D004307:Dose-Response Relationship, Radiation; D015972:Gene Expression Regulation, Neoplastic / Q000528:radiation effects; D006801:Humans; D007375:Interleukin-1 / Q000235:genetics / Q000378:metabolism / Q000528:radiation effects*; D007700:Kinetics; D012333:RNA, Messenger / Q000235:genetics; D013472:Sunlight; D014158:Transcription, Genetic / Q000528:radiation effects; D014466:Ultraviolet Rays
D007375:Interleukin-1; D012333:RNA, Messenger