title: The prevention of cataract caused by oxidative stress in cultured rat lenses. II. Early effects of photochemical stress and recovery.
abstract: Previous work has demonstrated that photochemically induced oxidative stress generated with 4 microM riboflavin in a 4% oxygen atmosphere utilizing daylight type radiation is capable of causing cataract in cultured rat lenses. Such cataract is prevented by the GSH peroxidase type mimic, AL-3823A. Examination of the early stages of cataract formation produced by short-term oxidative stress and recovery is now reported. A 24-hr oxidative stress, under the above conditions, causes loss of transparency, particularly in the equatorial region, increased hydration, loss of glyceraldehyde-3-PO4 dehydrogenase activity, oxidation of non-protein thiol and a decrease in 86Rb and [14C]choline uptake and ATP levels. Examination of recovery of these parameters during a 72-hr period indicates, in most cases, little or no reversal of oxidative damage. Hydration and loss of non-protein thiol continued during the recovery period. The presence of AL-3823A during the stress period prevented change in all parameters. Transport systems appear to be particularly vulnerable to this type of oxidative stress losing 50% or more activity within 4 hr. Even after a 2-hr stress, choline transport did not recover even though, under these conditions, ATP levels had only decreased slightly. Cytosolic components such as non-protein thiol and glyceraldehyde-3-PO4 dehydrogenase also showed little change after a 4-hr insult. 86Rb efflux experiments indicated no change in permeability during a 24-hr stress period. The overall conclusion from these studies is that a 24-hr oxidative stress which appears to reflect physiological conditions existing during cataract development, causes extensive, irreversible damage.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Ophthalmology, College of Physicians & Surgeons of Columbia University, New York, NY 10032.
authors.forename: A
authors.initials: A
authors.lastname: Spector
authors.forename: G M
authors.initials: GM
authors.lastname: Wang
authors.forename: R R
authors.initials: RR
authors.lastname: Wang
mesh_terms: D000818:Animals; D002386:Cataract / Q000209:etiology* / Q000378:metabolism; D046508:Culture Techniques; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000378:metabolism; D007908:Lens, Crystalline / Q000187:drug effects / Q000378:metabolism*; D008027:Light; D009942:Organometallic Compounds / Q000494:pharmacology*; D010084:Oxidation-Reduction; D051381:Rats; D017207:Rats, Sprague-Dawley; D012256:Riboflavin; D013312:Stress, Physiological / Q000150:complications*; D013438:Sulfhydryl Compounds / Q000378:metabolism
chemical_list: C080254:AL 3823A; D009942:Organometallic Compounds; D013438:Sulfhydryl Compounds; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D012256:Riboflavin