title: Effects of white light on beta-catenin signaling pathway in retinal pigment epithelium.
abstract: This study investigated the effect of visible light exposure on retinal pigment epithelium (RPE). The activation of Wnt/beta-catenin pathway was investigated by immunofluorescence and Western blot analysis using human retinal pigment epithelial (ARPE-19) cells, which demonstrated that the exposure of white light induced the activation of the Wnt/beta-catenin pathway. Real time RT-PCR demonstrated that the mRNA of alpha-smooth muscle actin (alpha-SMA), and vimentin increased 2.5-4-fold and that of zona occludens 1 (ZO-1) decreased approximately 0.8-fold after white light exposure. The up-regulation of vimentin expression and the down-regulation of ZO-1 were evident by Western blot analysis and immunohistochemistry. Moreover, the ability of phagocytosis of ARPE-19 cells decreased 0.6-fold after light exposure. Together, white light exposure was supposed to induce the activation of Wnt/beta-catenin pathway, the changes in the expression markers of epithelial and mesenchymal cells in RPE cells, and the concomitant impairment of the ability of phagocytosis.
authors.affiliation: Department of Ophthalmology, University of Tokyo School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.
authors.forename: Aya
authors.initials: A
authors.lastname: Iriyama
authors.forename: Takayuki
authors.initials: T
authors.lastname: Iriyama
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Tamaki
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Yanagi
mesh_terms: D000199:Actins / Q000096:biosynthesis; D002460:Cell Line; D004847:Epithelial Cells / Q000378:metabolism / Q000528:radiation effects; D006801:Humans; D008027:Light; D008565:Membrane Proteins / Q000096:biosynthesis; D008648:Mesoderm / Q000166:cytology / Q000378:metabolism / Q000528:radiation effects; D010587:Phagocytosis / Q000528:radiation effects; D010750:Phosphoproteins / Q000096:biosynthesis; D010857:Pigment Epithelium of Eye / Q000378:metabolism / Q000502:physiology / Q000528:radiation effects*; D015398:Signal Transduction / Q000528:radiation effects; D014746:Vimentin / Q000096:biosynthesis; D051153:Wnt Proteins / Q000378:metabolism*; D062826:Zonula Occludens-1 Protein; D051176:beta Catenin / Q000378:metabolism*
chemical_list: C541116:ACTA2 protein, human; D000199:Actins; D008565:Membrane Proteins; D010750:Phosphoproteins; C569042:TJP1 protein, human; D014746:Vimentin; D051153:Wnt Proteins; D062826:Zonula Occludens-1 Protein; D051176:beta Catenin