Effects of Radiofrequency Electromagnetic Fields and Ionizing Radiation on Amyloid Precursor Protein Processing and Cell Death

Abstract

The growing concerns regarding the adverse biological effects of radiofrequency electromagnetic fields (RF-EMFs), which are generated by common electronic devices, on the human brain led us to investigate their impact on Alzheimer’s disease (AD). We aimed to establish the effects of RF-EMF on the expression of molecular markers associated with amyloid precursor protein (APP), cell death, and clonogenic survival in HT22 and APP-overexpressing 7w-PSML cells. We compared the effects of RF-EMF at a high specific absorption rate (SAR) level with the neuronal-cell-death-inducing effects of ionizing radiation (IR). RF-EMF exposure (8 W/kg SAR) promoted the protein expression of ADAM10 (α-secretase) in the HT22 cells (<i>p</i> < 0.05) and downregulated the APP mRNA level in the 7w-PSML cells (<i>p</i> < 0.01). In contrast, IR (10 Gy) significantly reduced the APP and a disintegrin and metalloproteinase 10 (ADAM10) levels without altering their respective mRNA levels in these cells. Interestingly, IR exposure significantly upregulated BACE1 (α-secretase) at both the protein and mRNA levels, suggesting adverse effects in AD. IR induced cell death and reduced clonogenic survival in both cell lines. Although RF-EMF (high SAR level) influenced APP processing, it did not induce any deleterious change in either cell line. Thus, further studies are necessary to clarify the influence of RF-EMF on AD.