Effects of magnetic fields on the accumulation of thiobarbituric acid reactive substances induced by iron salt and H 2O 2 in mouse brain homogenates or phosphotidylcholine

Abstract

In this study, we examined the effects of magnetic fields (MFs) on the generation of thiobarbituric acid reactive substances (TBARS) in the mouse brain homogenates or phosphotidylcholine (PC) solution, incubated with FeCl 3 and/or H 2O 2. Active oxygen species were generated and lipid peroxidation was induced in mouse brain homogenates by incubation with iron ions, resulting in the accumulation of TBARS. Lipid peroxidation was induced in PC by incubation with iron ions and H 2O 2. Exposure to sinusoidal MFs (60 Hz, 0.2–1.2 mT), symmetric sawtooth-waveform MFs (50 Hz, 25–600 mT/s), rectangular MFs (1/0.4–1/16 Hz, 3.3 mT) and static MFs (1, 5–300 mT) had no effect on the accumulation of TBARS in brain homogenates induced by FeCl 3. In contrast, when the homogenates were incubated with FeCl 3 in static MFs (2–4 mT), the accumulation of TBARS was decreased. However, this inhibitory effect disappeared when EDTA was added to the homogenate and incubated with H 2O 2. The accumulation of TBARS in PC solution incubated with FeCl 3 and H 2O 2 was also inhibited by the static MF. These results indicate that only static MFs had an inhibitory effect on iron-induced lipid peroxidation and the effectiveness of this magnetic field on iron ion-induced active oxygen species generation is restricted to a so called ‘window’ of field intensity of 2–4 mT.