Gene Expression Profiles in White Blood Cells of Volunteers Exposed to a 50 Hz Electromagnetic Field

Abstract

Consistent and independently replicated laboratory evidence to support a causative relationship between environmental exposure to extremely low-frequency electromagnetic fields (EMFs) at power line frequencies and the associated increase in risk of childhood leukemia has not been obtained. In particular, although gene expression responses have been reported in a wide variety of cells, none has emerged as robust, widely replicated effects. DNA microarrays facilitate comprehensive searches for changes in gene expression without a requirement to select candidate responsive genes. To determine if gene expression changes occur in white blood cells of volunteers exposed to an ELF-EMF, each of 17 pairs of male volunteers age 20-30 was subjected either to a 50 Hz EMF exposure of 62.0 ± 7.1 μT for 2 h or to a sham exposure (0.21 ± 0.05 μT) at the same time (11:00 a.m. to 13:00 p.m.). The alternative regime for each volunteer was repeated on the following day and the two-day sequence was repeated 6 days later, with the exception that a null exposure (0.085 ± 0.01 μT) replaced the sham exposure. Five blood samples (10 ml) were collected at 2 h intervals from 9:00 to 17:00 with five additional samples during the exposure and sham or null exposure periods on each study day. RNA samples were pooled for the same time on each study day for the group of 17 volunteers that were subjected to the ELF-EMF exposure/sham or null exposure sequence and were analyzed on Illumina microarrays. Time courses for 16 mammalian genes previously reported to be responsive to ELF-EMF exposure, including immediate early genes, stress response, cell proliferation and apoptotic genes were examined in detail. No genes or gene sets showed consistent response profiles to repeated ELF-EMF exposures. A stress response was detected as a transient increase in plasma cortisol at the onset of either exposure or sham exposure on the first study day. The cortisol response diminished progressively on subsequent exposures or sham exposures, and was attributable to mild stress associated with the experimental protocol.

The effect of electromagnetic field on decreasing and increasing of the growth and proliferation rate of dermal fibroblast cell

“…In another study, Kirschenlohr et al showed that an extremely low-intensity EMF was also effective in expressing genes in white blood cells. 17 Moreover, according to the findings obtained by Gottwald et al, EMF is proved to be effective in the production of proteins in some cells. This factor along with other critical factors increases the growth and proliferation of cells.…”

Effects of single and combined low frequency electromagnetic fields and simulated microgravity on gene expression of human mesenchymal stem cells during chondrogenesis

“…Furthermore, we could show that LF-EMF application did not result in any gene expression changes of hMSCs during chondrogenic differentiation as examined by microarray analysis. This is of major importance as previous reports have linked EMF with an increased risk of carcinogenesis [ 16 – 18 ] and there is a growing concern in public health regarding EMF [ 36 ]. In this study, three weeks of LF-EMF did not cause any inadvertent gene expression changes.…”

“…Under Low frequency electromagnetic fields (LF-EMF), the chondrogenic differentiation of hMSCs in 3D culture showed a significant increase of collagen type II expression at higher cell passages, although no EMF effect was obtained under optimal differentiation conditions [ 15 ]. However, EMF have also been reported to cause adverse effects [ 16 – 18 ], and the level of concern about EMF in the general population is high. Among general practitioners, there is no association between correct knowledge and concern [ 19 ].…”

Electromagnetic Fields, Genomic Instability and Cancer: A Systems Biological View

“…Several research groups have investigated transcriptomic, proteomic, or metabolomic changes following exposure to ELF or RF electromagnetic fields. Earlier studies have been reviewed [63,64], and additional studies have been published recently [65,66,67,68,69,70,71,72]. There are many limitations in individual studies such as short exposure times, limited range of exposure levels, and limited number of sampling times after exposure.…”