A Simple Kinetic Model to Estimate Ascorbyl Radical Steady State Concentration in Rat Central Nervous System. Effect of Subchronic Fe Overload

Abstract

All biological systems, contain many antioxidants; including water-soluble compounds, such as ascorbic acid. The one-electron oxidation of ascorbate (AH¯produces the ascorbyl radical (A•), that has a relatively long lifetime compared to other species, such as hydroxyl radical, peroxyl, alkoxyl, and carbon-centered lipid free radicals. A• has been proposed as a marker of oxidative stress either in vitro, or in vivo in numerous systems. The application of a simple kinetic analysis allowed us to estimate the steady state concentration of A•. These data were successfully compared to experimental values obtained using Electron Paramagnetic Resonance (EPR) in rat brain under physiological conditions. The model was also applied to estimate the response to stress due to subchronic Fe overload.