title: Irradiance, but not fluence, plays a crucial role in UVB-induced immature pigment cell development: new insights for efficient UVB phototherapy.
abstract: Light exposure modulates development of living organisms. In the field of medicine, light has frequently been used for regenerative purposes. Excimer light (308 nm) has demonstrated superior efficacy in treating vitiligo, a condition requiring development of melanoblasts and a model for studying nerve cell regeneration, as compared to narrow-band ultraviolet B (NBUVB; 311 nm). Using mouse-derived melanoblast cells to examine the pro-differentiation effects of these two light sources, we demonstrated that at equivalent fluence, excimer light induces melanoblast differentiation, while NBUVB failed to so. Mechanistically, activation of aryl hydrocarbon receptor pathway and nuclear translocation of epidermal growth factor receptor are involved in pro-differentiation effects of excimer light. Reduction in irradiance by filter abrogated the effects of excimer light in melanoblasts, even when equivalent fluence was delivered by the same light source. As ultraviolet B (UVB) irradiation is closely associated pigment cell development, future therapy employing UVB for pigmentation purposes should incorporate irradiance as a crucial specification.
authors: Department of Dermatology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
authors: Cheng-Che E
authors: CC
authors: Lan
authors: Hsin-Su
authors: HS
authors: Yu
authors: Jian-He
authors: JH
authors: Lu
authors: Ching-Shuang
authors: CS
authors: Wu
authors: Hsiao-Chi
authors: HC
authors: Lai
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000528:radiation effects*; D002467:Cell Nucleus / Q000378:metabolism; D002470:Cell Survival / Q000528:radiation effects; D047369:Chromatin Immunoprecipitation; D019363:Cytochrome P-450 CYP1A1 / Q000096:biosynthesis / Q000235:genetics; D004705:Endocytosis / Q000528:radiation effects; D004790:Enzyme Induction / Q000528:radiation effects; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic / Q000528:radiation effects; D020868:Gene Silencing / Q000528:radiation effects; D007150:Immunohistochemistry; D008544:Melanocytes / Q000166:cytology* / Q000201:enzymology / Q000528:radiation effects*; D051379:Mice; D014442:Monophenol Monooxygenase / Q000096:biosynthesis / Q000235:genetics; D010858:Pigmentation / Q000528:radiation effects*; D011401:Promoter Regions, Genetic / Q000235:genetics; D021381:Protein Transport / Q000528:radiation effects; D011740:Pyrimidine Dimers / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018336:Receptors, Aryl Hydrocarbon / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic / Q000528:radiation effects; D014466:Ultraviolet Rays; D014467:Ultraviolet Therapy; D019061:src-Family Kinases / Q000378:metabolism
chemical_list: D011740:Pyrimidine Dimers; D012333:RNA, Messenger; D018336:Receptors, Aryl Hydrocarbon; D019363:Cytochrome P-450 CYP1A1; D014442:Monophenol Monooxygenase; D066246:ErbB Receptors; D019061:src-Family Kinases