Interaction of Glutathione with Hydrogen Peroxide: A Kinetic Model

Abstract

The kinetics of the interaction of glutathione (GSH) with hydrogen peroxide (H₂O₂) was studied. It was shown that the rate of GSH consumption nonlinearly depended on reactant concentrations and the process was accompanied by the appearance of radicals with a relatively low rate, which was a fraction of a percent of the rate of GSH consumption. Based on the experimental results and literature data on the reactions of GSH with H₂O₂ and thiyl radicals, a kinetic model of the complex interaction of GSH and H₂O₂ in an aqueous solution at 37°C was proposed. The model includes 15 quasi-elementary reactions with corresponding rate constants, including the formation of the intermediate complex GSH–H₂O₂ and its subsequent reactions with the formation of final products. Computer simulation based on the model developed satisfactorily described the reaction kinetics in a wide range of reactant concentrations.