To study the influence of extremely low frequency electromagnetic fields on protein oxidation and on the 20S proteasome functionality (the complex responsible for the degradation of oxidized proteins). Furthermore, epigallocatechin-3-gallate (EGCG) protective action towards extremely low frequency electromagnetic fields mediated oxidative damage has been also evaluated.
Epigallocatechin-3-gallate is a natural compound (the major component of green tea) with antioxidant properties.
Cells were cultured in the presence and absence of EGCG and in the presence and absence of TPA.
|Exposure duration||continuous for 24 hr to 72 hr|
|Setup||40 cm long solenoid with a diameter of 20 cm with 3 forward-backward-forward layers of 600 turns of 2 mm diameter copper wire inside a water-jacketed temperature and atmosphere regulated incubator; 11 cm x 17 cm exposure volume along the axis with a field variation of 5 %|
|Sham exposure||A sham exposure was conducted.|
The exposure induced a time-dependent increase both in cell growth and in protein oxidation, more evident in the presence of TPA, while no changes in cell viability were detected. The results showed that the electromagnetic fields are able to affect the proteasome functionality inducing an increase in its proteolytic activity (particularly evident at 72 hours exposure and in the presence of TPA). The finding that epigallocatechin-3-gallate counteracts the electromagnetic fields related pro-oxidant effects demonstrate that this increase in proteasome activity is due to an increase in intracellular free radicals.