Superposed Electromagnetic Noise Blocks ROS Increase And DNA Damage Of Cultured Lens Epithelial Cells Induced By Microwave Radiation

Partâ… Superposed electromagnetic noise blocks ROS increase and DNA damage of cultured lens epithelial cells induced by chronic microwave radiationObjectiveTo investigate the influence of the chronic 1.8 GHz radiofrequency fields(RF) of the Global System for Mobile Communications(GSM) on DNA damage,intracellular reactive oxygen species(ROS) formation,cell cycle and apoptosis in human lens epithelial cells (hLECs),and whether the effects induced by RF could be blocked by superposing of electromagnetic noise.MethodsAfter 24 h intermittent exposure at the specific absorption rate(SAR) of 1,2,3,4 W/kg,the DNA damage of hLECs was examined by alkaline comet assay and immunofluorescent microscope detection of the phosphorylated form of histone variant H2AX(γH2AX) foci, respectively.ROS production was quantified by the fluorescent probe 2',7'-dichlorodihydrofluorescein diacetate(DCFH-DA).The cell cycle and cell apoptosis were determined by flow cytometry.ResultsDNA damage examined by alkaline comet assay was significantly increased after 3 W/kg and 4 W/kg radiation(P＜0.05),while the double strand breaks(DSBs) evaluated byγH2AX foci were significantly increased only after 4 W/kg radiation(P＜0.05).Significantly elevated intracellular ROS levels were also detected in the 3 W/kg and 4 W/kg groups(P＜0.05).After exposure to 4 W/kg for 24 h,hLEC exhibited significant G₀/G₁ arrest(P＜0.05).There was no detectable difference in cell apoptosis between the microwave radiation and sham exposure groups(P＞0.05).All the effects mentioned above were blocked when the RF was superposed with 2μT electromagnetic noise.ConclusionsMicrowave radiation(MR) induced hLEC DNA damage following G₀/G₁ arrest does not lead to cell apoptosis.The increased ROS which was observed may be associated with the DNA damage.Superposed electromagnetic noise blocks microwave radiation-induced DNA damage, ROS formation and cell cycle arrest.Partâ…¡Superposed electromagnetic noise inhibits ROS increase and DNA damage of cultured lens epithelial cells induced by acute microwave radiationObjectiveThe goal of this study was to investigate whether superposing of electromagnetic noise could inhibit or attenuate DNA damage and intracellular reactive oxygen species(ROS) increase in cultured human lens epithelial cells(hLECs) induced by acute exposure to 1.8 GHz radiofrequency field(RF) of the Global System for Mobile Communications(GSM).MethodsAn sXc-1800 RF exposure system was used to produce a GSM signal at 1.8 GHz(217 Hz amplitude-modulated) with the specific absorption rate(SAR) of 1,2,3 and 4 W/kg.After 2 h intermittent exposure,the ROS level was assessed by the fluorescent probe 2',7'-dichlorodihydrofluorescein diacetate(DCFH-DA).The DNA damage of hLEC was examined by alkaline comet assay and the phosphorylated form of histone variant H2AX (γH2AX) foci formation assay,respectively.ResultsAfter exposure to 1.8 GHz RF for 2 h,hLECs exhibited significant intracellular ROS increase in the 2,3 and 4 W/kg groups.RF radiation at the SAR of 3 W/kg and 4 W/kg could induce significant DNA damage examined by alkaline comet assay,which was used to detect mainly single strand breaks(SSBs),while no statistical difference of double strand breaks (DSBs) evaluated byγH2AX foci was found between RF exposure(SAR,3 and 4 W/kg) and sham exposure groups.Superposed with 2μT electromagnetic noise could block RF-induced ROS increase and DNA damage.ConclusionsDNA damage induced by 1.8 GHz radiofrequency field for 2 h,which was mainly SSB, may be associated with the increased ROS production.Electromagnetic noise could inhibit RF-induced ROS formation and DNA damage.