Pulsed electromagnetic fields affect the intracellular calcium concentrations in human astrocytoma cells

Abstract

Experiments assessed whether long term exposure to 50 Hz pulsed electromagnetic fields with a peak magnetic field of 3 mT can alter the dynamics of intracellular calcium in human astrocytoma U-373 MG cells. Pretreatment of cells with 1.2 microM substance P significantly increased the [Ca(2+)](i). The same effect was also observed when [Ca(2+)](i) was evaluated in the presence of 20 mM caffeine. After exposure to electromagnetic fields the basal [Ca(2+)](i) levels increased significantly from 143 +/- 46 nM to 278 +/- 125 nM. The increase was also evident after caffeine addition, but in cells treated with substance P and substance P + caffeine we observed a [Ca(2+)](i) decrease after exposure. When we substituted calcium-free medium for normal medium immediately before the [Ca(2+)](i) measurements, the [Ca(2+)](i) was similar to that measured in the presence of Ca(2+). In this case, after EMFs exposure of cells treated with substance P, the [Ca(2+)](i), measured without and with addition of caffeine, declined from 824 +/- 425 to 38 +/- 13 nM and from 1369 +/- 700 to 11 +/- 4 nM, respectively, indicating that electromagnetic fields act either on intracellular Ca(2+) stores or on the plasma membrane. Moreover the electromagnetic fields that affected [Ca(2+)](i) did not cause cell proliferation or cell death and the proliferation indexes remained unchanged after exposure.

Cellular target of weak magnetic fields: ionic conduction along actin filaments of microvilli

“…Experiments with different cell types consistently point to the Ca 2ϩ signaling system as the primary cellular target of MF interactions (5,10,23,52,53,60,69,86,87). In many cases, alternating MFs alone or in combination with static fields increase intracellular Ca 2ϩ , as, for instance, in HL60 cells (10), T-lymphocytes and leukemia cells (60), the human T cell line (Jurkat) (55,56), bone cells (23), pituitary cells (5), and human astrocytoma cells (69).…”

“…In many cases, alternating MFs alone or in combination with static fields increase intracellular Ca 2ϩ , as, for instance, in HL60 cells (10), T-lymphocytes and leukemia cells (60), the human T cell line (Jurkat) (55,56), bone cells (23), pituitary cells (5), and human astrocytoma cells (69).…”

Electromagnetic Field Exposure and Male Breast Cancer Risk: A Meta-analysis of 18 Studies

“…Besides the effect on melatonin, EMF damage in genetic and other research level has been discussed also. It has been proposed that EMF theoretically is not able to produce sufficient energy to break DNA molecules or other chemical bonds, but may have a direct genotoxic effect in exposed persons, or disturb the concentration of intracellular calcium ion and the 6-hydroxy melatonin sulfate (Davis et al, 2001;Nordenson et al, 2001;Pessina et al, 2001;Zhang et al, 2010). But these hypotheses have not gained firm support from experimental researches because of conflicting results (Forssen et al, 2000;Christoffer, 2004;Chen et al, 2010).…”

The Effects of Extremly Low Frequency Magnetic Field and Mangan to the Oral Tissues

“…While there are studies which showed that it activates bone formation and development, inhibits osteoclastic activity, contributes to the healing process of bone fractures, helps granulation and fibrous tissue formation in wound healing, and that dwelling close to ELFMF on its effects over dental tissues and mineral structures. While a study indicated ELFMF as non-would not be a risk, there are also studies indicating that it affects immune system, induces carcinogenic effects such as leukemia, and generates neurologic diseases, endocrine system disorders, degenerative heart diseases, vascular damage, and emphysema in lungs (3,4,6,8,10,11,12,13,15,16,18,20). There are very limited number of studies conducted influential on clinical and laboratory.…”