Correlation between ELF–PEMF exposure and Human RPE Cell Proliferation, Apoptosis and Gene Expression


Purpose: Emerging evidence implies that electromagnetic fields (EMFs) can negatively affect angiogenesis. In this regard, the effects of extremely low frequency pulsed electromagnetic field (ELF–PEMF) exposure on the relative expression level of angiogenic factors involved in the pathogenesis of ocular disorders were evaluated in human retinal pigment epithelial (hRPE) cells in order to investigate a noninvasive therapeutic method for patients with several ocular diseases associated with neovascularization.

Methods: After separating hRPE cells from globes, hRPE cells were exposed to 15 mT of ELF–PEMF (120 Hz) at 5, 10, and 15 min for seven days. Cell proliferation and apoptosis of treated cells were evaluated via ELISA assay. Moreover, relative expression changes of HIF-1α, CTGF, VEGFA, MMP-2, cathepsin D, and E2F3 were performed using real-time RT-PCR.

Results: ELF–PEMF exposure had no significant effects on the apoptosis and proliferation rate of hRPE cells. Expression level of HIF-1α, CTGF, VEGFA, MMP- 2, cathepsin D, and E2F3 was downregulated following 5 min of ELF–PEMF exposure.

Conclusion: As ELF–PEMF showed inhibitory effects on the expression of angiogenic genes in hRPE cells with no cytotoxic or proliferative side effects, it can be introduced as a useful procedure for managing angiogenesis induced by retinal pathogenesis, although more studies with adequate follow-up in animal models are needed.


Angiogenic Factors, ELF–PEMFs, hRPE Cells

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