Ultraviolet radiation-induced corneal degeneration in 129 mice.
Ultraviolet radiation (UVR) is a risk factor for the development of ocular disease in humans, including acute photokeratitis, chronic corneal spheroidal degeneration, and cataract formation. This report describes the ocular lesions seen in 21 mice chronically exposed to UVR as part of a skin carcinogenicity study. All globes were affected to varying degrees. The primary lesion, not previously reported in UVR-exposed mice, was marked loss of keratocytes relative to age-matched controls. Secondary lesions included corneal stromal thinning, keratoconus, corneal vascularization and fibrosis, keratitis, globe rupture, and phthisis bulbi. In addition, more than 90% of UVR-exposed and unexposed lenses had evidence of cataract formation; this is the first report of the occurrence of spontaneous cataracts in 129 mice. In a subsequent study, apoptotic cells were identified histologically and by cleaved caspase 3 immunoreactivity in the corneal epithelium and, less commonly, in the corneal stroma after acute UVR exposure. Based on this finding, we propose that the loss of keratocytes observed in the chronic study was due to UVR-induced apoptosis.
Newkirk
Kimberly M
KM
Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, Ohio 43210, USA. kmnewkirk@mail.ag.utk.edu
Chandler
Heather L
HL
Parent
Allison E
AE
Young
Donn C
DC
Colitz
Carmen M H
CM
Wilkie
David A
DA
Kusewitt
Donna F
DF
D000444:Aldehyde Dehydrogenase / Q000502:physiology; D000818:Animals; D002386:Cataract / Q000209:etiology; D003315:Cornea / Q000473:pathology / Q000528:radiation effects*; D005260:Female; D008297:Male; D020782:Matrix Metalloproteinases / Q000502:physiology; D051379:Mice; D017382:Reactive Oxygen Species / Q000378:metabolism; D014466:Ultraviolet Rays
D017382:Reactive Oxygen Species; D000444:Aldehyde Dehydrogenase; D020782:Matrix Metalloproteinases