High-resolution MAS 1H NMR spectroscopic analysis of rabbit cornea after treatment with dexamethasone and exposure to UV-B radiation.
Metabolic changes in rabbit cornea after combined long-term steroid treatment and UV-B exposure were investigated. Corneas were exposed to UV-B radiation (2.05 J/cm2) after 36 days topical pretreatment with either 0.1% dexamethasone or saline. Twenty-four hours after UV-B exposure, corneas were excised and aqueous humour aspirated. Intact corneal tissues were analyzed by magic angle spinning proton NMR spectroscopy and pattern recognition methods. UV-B decreased corneal ascorbate (63% reduction), taurine (62%), and choline (63%), whereas glucose was elevated. Dexamethasone pretreatment further depleted corneal taurine and ascorbate, decreased aqueous ascorbate (85%), and accumulated glucose in cornea and aqueous humour. The results reflect antioxidative mechanisms and osmoregulation.
Saether
Oddbjørn
O
Department of Ophthalmology, Norwegian University of Science and Technology (NTNU), Trondheim, Norway. oddbjorn.sather@ntnu.no
Krane
Jostein
J
Risa
Øystein
Ø
Cejková
Jitka
J
Midelfart
Anna
A
D000818:Animals; D001205:Ascorbic Acid / Q000378:metabolism; D002794:Choline / Q000378:metabolism; D003315:Cornea / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects; D003907:Dexamethasone / Q000494:pharmacology*; D005938:Glucocorticoids / Q000494:pharmacology*; D005947:Glucose / Q000378:metabolism; D019906:Nuclear Magnetic Resonance, Biomolecular; D011817:Rabbits; D013654:Taurine / Q000378:metabolism; D014466:Ultraviolet Rays; D014882:Water-Electrolyte Balance
D005938:Glucocorticoids; D013654:Taurine; D003907:Dexamethasone; D005947:Glucose; D002794:Choline; D001205:Ascorbic Acid