Effect of 50Hz Extremely Low-Frequency Electromagnetic Fields on the DNA Methylation and DNA Methyltransferases in Mouse Spermatocyte-Derived Cell Line GC-2

Previous studies have shown that the male reproductive system is one of the most sensitive organs to electromagnetic radiation. However, the biological effects and molecular mechanism are largely unclear. Our study was designed to elucidate the epigenetic effects of 50Hz ELF-EMF in vitro. Mouse spermatocyte-derived GC-2 cell line was exposed to 50Hz ELF-EMF (5 min on and 10min off) at magnetic field intensity of 1mT, 2mT, and 3mT with an intermittent exposure for 72 h. We found that 50 Hz ELF-EMF exposure decreased genome-wide methylation at 1mT, but global methylation was higher at 3mT compared with the controls. The expression of DNMT1 and DNMT3b was decreased at 1mT, and 50Hz ELF-EMF can increase the expression of DNMT1 and DNMT3b of GC-2 cells at 3mT. However, 50Hz ELF-EMF had little influence on the expression of DNMT3a. Then, we established DNA methylation and gene expression profiling and validated some genes with aberrant DNA methylation and expression at different intensity of 50Hz ELF-EMF. These results suggest that the alterations of genome-wide methylation and DNMTs expression may play an important role in the biological effects of 50Hz ELF-EMF exposure.