Antioxidant capacity of desferrioxamine in biological systems

The antioxidant capacity of desferrioxamine (DF) was investigated in three biological systems. The addition of DF to rat brain homogenates undergoing autoxidation elicited a concentration dependent inhibition of both oxygen uptake and chemiluminescence, with a median inhibitory concentration (IC50) of 0.52 microM. In this system, Fe3+-induced light emission was completely abolished at a DF/Fe3+ molar ratio of 0.6. In rat erythrocyte suspensions supplemented with t-butyl hydroperoxide, DF lengthened the induction period and decreased the rate of oxygen consumption, with an IC50 of 300 microM. Infusion of increasing concentrations of DF to the perfused rat liver elicited a progressive decrease in the rate of oxygen consumption, with no alterations in the mitochondrial respiration. This DF-sensitive respiration has a maximal value of 200 nmol/g of liver/min, with a half-maximal rate at 120 microM DF. These results indicate that DF behaves as an efficient antioxidant either under basal conditions or in chemically-induced oxidative stress, through Fe3+ chelating and/or free-radical scavenging effects.