Increase in Fe3+/Fe2+ Ratio and Iron-Induced Oxidative Stress in Eales Disease and Presence of Ferrous Iron in Circulating Transferrin

Eales disease was shown to be associated with oxidant stress and weak antioxidant defense. Total iron, ferrous iron, thiobarbituric acid reactive substances (TBARS), and ceruloplasmin were estimated in the blood samples of patients with inflammation, perivasculitis, and venous insufficiency. Levels of ferric iron were determined from the difference in those of total iron and ferrous iron. All biochemical parameters were estimated in age and sex-matched controls. Fe3+/Fe2+ ratio was greater in patients with Eales disease than in normal controls. Similar increase in TBARS and ceruloplasmin levels were noted. The patients were treated with prednisone and vitamins E and C, then Fe3+/Fe2+ ratios and TBARS decreased progressively; the active state of the disease was reduced to 16%. So Fe3+/Fe2+ ratio in addition to TBARS levels could be considered an index of the active state of the disease. Circulating transferrin in blood did contain ferrous iron. Binding of ferrous iron to transferrin was confirmed by estimating iron-binding capacity using ferrous ammonium sulphate.