Isoflavones prevent oxidative stress and inhibit the activity of the enzyme monoamine oxidase in vitro.

Oxidative stress occurs due to an imbalance between antioxidant defenses and pro-oxidant agents in brain. This condition has been associated to the pathogenesis of several brain diseases; therefore, increasing the use of compounds that exert antioxidant activity. Thus, the objective of this study was to evaluate, in vitro, the effect of isoflavones in: (1) lipid peroxidation, catalase activity and thiol groups in the presence of pro-oxidants: sodium nitroprusside or Fe/EDTA complex in rat brain homogenates; (2) the activity of the enzyme monoamine oxidase (MAO).