G Sevin1, Z Kerry, N Sozer, G Ozsarlak-Sozer. 1. Department of Pharmacology, Faculty of Pharmacy, Ege University, Bornova, Izmir, Turkey. gonen.ozsarlak@ege.edu.tr.
Abstract
OBJECTIVE: Cataract which is defined as opacification of eye lens forms approximately 40% of total blindness causes all through the world. Age is the biggest risk factor for cataracts and oxidative stress is known to be one of the most important factors causing cataract formation. Age-related nuclear cataract (ARN) is associated with a loss of glutathione in the center of the lens. Taurine is an important antioxidant in lens tissue. Although, there is a high amount of taurine in lenses in early life, its concentration declines with age. In this study, we aimed to investigate the effects of supplemental taurine in lens tissues in an in vivo oxidative stress model which is induced by glutathione depletion to mimic ARN. MATERIALS AND METHODS: Glutathione depletion was induced in rabbits subcutaneously with l-Buthionine -(S,R)-sulfoximine (BSO)- a glutathione inhibitor and the rabbits were treated with taurine. Total GSH, reduced GSH, GSH/GSSG ratio and MDA levels were measured. RESULTS: BSO lowered the reduced GSH and total GSH levels and GSH/GSSG ratio. Taurine reversed these effects. On the other hand, BSO enhanced MDA level which is normalized by taurine. CONCLUSIONS: These findings suggest that glutathione depletion with BSO may be a useful model to mimic ARN and dietary intake of taurine, may have an important role in decelerating the process of cataract formation.
OBJECTIVE: Cataract which is defined as opacification of eye lens forms approximately 40% of total blindness causes all through the world. Age is the biggest risk factor for cataracts and oxidative stress is known to be one of the most important factors causing cataract formation. Age-related nuclear cataract (ARN) is associated with a loss of glutathione in the center of the lens. Taurine is an important antioxidant in lens tissue. Although, there is a high amount of taurine in lenses in early life, its concentration declines with age. In this study, we aimed to investigate the effects of supplemental taurine in lens tissues in an in vivo oxidative stress model which is induced by glutathione depletion to mimic ARN. MATERIALS AND METHODS: Glutathione depletion was induced in rabbits subcutaneously with l-Buthionine -(S,R)-sulfoximine (BSO)- a glutathione inhibitor and the rabbits were treated with taurine. Total GSH, reduced GSH, GSH/GSSG ratio and MDA levels were measured. RESULTS: BSO lowered the reduced GSH and total GSH levels and GSH/GSSG ratio. Taurine reversed these effects. On the other hand, BSO enhanced MDA level which is normalized by taurine. CONCLUSIONS: These findings suggest that glutathione depletion with BSO may be a useful model to mimic ARN and dietary intake of taurine, may have an important role in decelerating the process of cataract formation.