Protective effect of melatonin against in vitro iron ions and 7 mT 50 Hz magnetic field-induced DNA damage in rat lymphocytes med./bio.

To study the effect of melatonin, an established free radical scavenger, on DNA damage in rat peripheral blood lymphocytes exposed in vitro to iron ions and 50 Hz magnetic field.

The authors have previously shown that simultaneous exposure of rat lymphocytes to iron ions and 50 Hz magnetic field caused an increase in the number of cells with DNA damage (publication 4790). Although the mechanism of magnetic-induced DNA damage is not known, the authors suppose that it involves free radicals.
During pre-incubation, part of the cell samples were supplemented with melatonin (0.5 or 1.0 mM). During magnetic field exposure, some samples were treated with ferrous chloride (FeCl₂, 10 µg/ml), while the rest served as controls.

• intact cell/cell culture
• rat lymphocytes

A significant increase in the number of cells with DNA damage was found only after simultaneous exposure of lymphocytes to FeCl₂ and magnetic field, compared to the control samples or those incubated with FeCl₂ alone. However, when the lymphocytes were treated with melatonin and then exposed to iron ions and magnetic field, the number of damaged cells was significantly reduced. The effect depended on the concentration of melatonin: The reduction reached about 50% at 0.5 mM and about 100% at 1.0 mM.
The data indicate that melatonin provides protection against DNA damage in rat lymphocytes exposed in vitro to iron ions and 50 Hz magnetic field. Therefore, it can be suggested that free radicals may be involved in 50 Hz magnetic field and iron ions-induced DNA damage.