title: Influence of Light Emitting Diode-Derived Blue Light Overexposure on Mouse Ocular Surface.
abstract: OBJECTIVE
  To investigate the influence of overexposure to light emitting diode (LED)-derived light with various wavelengths on mouse ocular surface.
  
  
  METHODS
  LEDs with various wavelengths were used to irradiate C57BL/6 mice at an energy dose of 50 J/cm2, twice a day, for 10 consecutive days. The red, green, and blue groups represented wavelengths of 630 nm, 525 nm, and 410 nm, respectively. The untouched group (UT) was not exposed to LED light and served as the untreated control. Tear volume, tear film break-up time (TBUT), and corneal fluorescein staining scores were measured on days 1, 3, 5, 7, and 10. Levels of interferon (IFN)-γ, interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α were measured in the cornea and conjunctiva using a multiplex immunobead assay at day 10. Levels of malondialdehyde (MDA) were measured with an enzyme-linked immunosorbent assay. Flow cytometry, 2'7'-dichlorofluorescein diacetate (DCF-DA) assay, histologic analysis, immunohistochemistry with 4-hydroxynonenal, and terminal deoxynucleotidyl transferase-mediated dUTP-nick end labeling (TUNEL) staining were also performed.
  
  
  RESULTS
  TBUT of the blue group showed significant decreases at days 7 and 10, compared with the UT and red groups. Corneal fluorescein staining scores significantly increased in the blue group when compared with UT, red, and green groups at days 5, 7, and 10. A significant increase in the corneal levels of IL-1β and IL-6 was observed in the blue group, compared with the other groups. The blue group showed significantly increased reactive oxygen species production in the DCF-DA assay and increased inflammatory T cells in the flow cytometry. A significantly increased TUNEL positive cells was identified in the blue group.
  
  
  CONCLUSIONS
  Overexposure to blue light with short wavelengths can induce oxidative damage and apoptosis to the cornea, which may manifest as increased ocular surface inflammation and resultant dry eye.
authors: Department of Ophthalmology, Chonnam National University Medical School and Hospital, Gwangju, South Korea.
authors: Hyo Seok
authors: HS
authors: Lee
authors: Department of Ophthalmology, Chonnam National University Medical School and Hospital, Gwangju, South Korea.|Department of Biomedical Sciences and Center for Creative Biomedical Scientists, Chonnam National University, Gwangju, South Korea.
authors: Lian
authors: L
authors: Cui
authors: Department of Ophthalmology, Chonnam National University Medical School and Hospital, Gwangju, South Korea.|Department of Biomedical Sciences and Center for Creative Biomedical Scientists, Chonnam National University, Gwangju, South Korea.
authors: Ying
authors: Y
authors: Li
authors: Department of Ophthalmology, Chonnam National University Medical School and Hospital, Gwangju, South Korea.
authors: Ji Suk
authors: JS
authors: Choi
authors: College of Veterinary Medicine and BK 21 PLUS Project Team, Chonnam National University, Gwangju, South Korea.
authors: Joo-Hee
authors: JH
authors: Choi
authors: Department of Ophthalmology, Chonnam National University Medical School and Hospital, Gwangju, South Korea.|Xiamen Eye Center of Xiamen University, Xiamen, Fujian, China.
authors: Zhengri
authors: Z
authors: Li
authors: Department of Pathology, Chonnam National University Medical School and Hospital, Gwangju, South Korea.
authors: Ga Eon
authors: GE
authors: Kim
authors: Department of Ophthalmology, Chonnam National University Medical School and Hospital, Gwangju, South Korea.
authors: Won
authors: W
authors: Choi
authors: Department of Ophthalmology, Chonnam National University Medical School and Hospital, Gwangju, South Korea.
authors: Kyung Chul
authors: http://orcid.org/0000-0002-2788-1851
authors: KC
authors: Yoon
mesh_terms: D000818:Animals; D002452:Cell Count; D003228:Conjunctiva / Q000166:cytology; D003315:Cornea / Q000528:radiation effects; D005123:Eye / Q000166:cytology / Q000378:metabolism / Q000528:radiation effects*; D005260:Female; D020397:Goblet Cells / Q000166:cytology / Q000528:radiation effects; D008027:Light; D051379:Mice; D008810:Mice, Inbred C57BL; D017382:Reactive Oxygen Species / Q000378:metabolism; D012666:Semiconductors; D013499:Surface Properties; D013666:Tears / Q000378:metabolism / Q000528:radiation effects
chemical_list: D017382:Reactive Oxygen Species