Protective effects of selenium, vitamin C and vitamin E against oxidative stress of cigarette smoke in rats

Cataractous lenses have been found to have an alter ed distribution of the intracellular ionice environment: the concentrations of potassium and magne sium being decreased and the concentrations of sodium and calcium increased . These changes arise as a result of changes to lens membrane characteristi cs causing an increase in lens membrane permeability. In this study flame atomic absorption spectroscopy (AAS) was used for calci um, magnesium, iron and zinc determination, and flame atomic emission spect roscopy (AES) was used for sodium and potassium contents in normal and ciga rette smoke-exposed rat lenses. The methods are sensitive enough to detect quantitatively all six cations in a single rat lenses, In this work, six el ements, including Ca2+, K+, Na+, Zn2+, Fe2+ and Mg2+ in experimental rat ey e lenses and normal transparent lenses were determined. It was found that t he concentrations of Ca2+, Na+, Zn2+, and Fe2+ were increased dramatically while K+ and Mg2+ decreased in smoke-exposed rat lenses when compared to th e control rat lenses. There were no significant changes between 'smoked' ra ts supplied with vitamin C and control groups. A positive correlation was f ound also in the other two groups of 'cigarette smoked' animals supplemente d with selenium plus vitamin E and selenium when compared with 'cigarette s moked' without any supplements. These data provide support for the hypothes is that cigarette smoking increases the risk of cataract formation. We inve stigated whether vitamin C is the most important antioxidant in the body. T he roles of diet with optimum amounts of antioxidant vitamins C and vitamin E and the antioxidant mineral selenium are discussed. Copyright (C) 1999 J ohn Wiley & Sons. Ltd.