title: Red light interferes in UVA-induced photoaging of human skin fibroblast cells.
abstract: The possible regulation mechanism of red light was determined to discover how to retard UVA-induced skin photoaging. Human skin fibroblasts were cultured and irradiated with different doses of UVA, thus creating a photoaging model. Fibroblasts were also exposed to a subtoxic dose of UVA combined with a red light-emitting diode (LED) for five continuous days. Three groups were examined: control, UVA and UVA plus red light. Cumulative exposure doses of UVA were 25 J cm(-2), and the total doses of red light were 0.18 J cm(-2). Various indicators were measured before and after irradiation, including cell morphology, viability, β-galactosidase staining, apoptosis, cycle phase, the length of telomeres and the protein levels of photoaging-related genes. Red light irradiation retarded the cumulative low-dose UVA irradiation-induced skin photoaging, decreased the expression of senescence-associated β-galactosidase, upregulated SIRT1 expression, decreased matrix metalloproteinase MMP-1 and the acetylation of p53 expression, reduced the horizon of cell apoptosis and enhanced cell viability. Furthermore, the telomeres in UVA-treated cells were shortened compared to those of cells in the red light groups. These results suggest that red light plays a key role in the antiphotoaging of human skin fibroblasts by acting on different signaling transduction pathways.
authors.affiliation: Aviation Medicine Research Laboratory, The General Hospital of the Air Force, Beijing, China.
authors.forename: Tianhui
authors.initials: T
authors.lastname: Niu
authors.forename: Yan
authors.initials: Y
authors.lastname: Tian
authors.forename: Qu
authors.initials: Q
authors.lastname: Ren
authors.forename: Lizhao
authors.initials: L
authors.lastname: Wei
authors.forename: Xiaoxin
authors.initials: X
authors.lastname: Li
authors.forename: Qing
authors.initials: Q
authors.lastname: Cai
mesh_terms: D002478:Cells, Cultured; D005347:Fibroblasts / Q000166:cytology / Q000201:enzymology / Q000528:radiation effects; D006801:Humans; D020935:MAP Kinase Signaling System; D015595:Skin Aging / Q000528:radiation effects*; D016615:Telomere; D014466:Ultraviolet Rays