Lyn and Syk tyrosine kinases are not activated in B‐lineage lymphoid cells exposed to low‐energy electromagnetic fields

Abstract

Exposure of B-lineage lymphoid cells to a 100 microT 60 Hz AC magnetic field has been reported to stimulate the rapid activation of Lyn and Syk tyrosine kinases and the induction of protein tyrosine phosphorylation. These findings are significant because of the critical role played by these B cell signaling events in the control of growth and differentiation, and therefore the potential of electromagnetic field (EMF) exposure to induce cancer. We report the first study carried out with the aim of reproducing the reported EMF effects on Lyn and Syk tyrosine kinases. The system used enabled EMF exposure conditions to be carefully controlled and also allowed experiments to be performed blind. The effects of a 100 microT 60 Hz AC magnetic field on protein tyrosine phosphorylation and on Lyn and Syk tyrosine kinase activities were investigated in Nalm-6 and DT40 B cells in the absence and presence of a 46 microT DC magnetic field. However, no significant effects of low-energy electromagnetic fields on tyrosine kinase activities or protein phosphorylation were observed.

Non-thermal activation of the hsp27/p38MAPK stress pathway by mobile phone radiation in human endothelial cells: Molecular mechanism for cancer- and blood-brain barrier-related effects

“…are changes in protein phosphorylation and activation of stress response (Ono and Han, 2000). There are several published studies examining effects of electromagnetic fields (60 Hz) on protein phosphorylation and activity of stress proteins and kinases (Pipkin et al, 1999; Jin et al, 2000; Morehouse and Owen, 2000; Woods et al, 2000; Wetzel et al, 2001). However, results of these studies are not directly applicable for the clarification of the possible biological and health effects of the RF‐EMF radiation emitted by mobile phones.…”

Electromagnetic fields affect transcript levels of apoptosis‐related genes in embryonic stem cell‐derived neural progenitor cells

“…In vitro studies showed molecular and cellular reactions in response to ELF-EMF exposure, including increase of apoptosis (16), the induction of DNA breaks (17), increased intracellular calcium (18) and gene expression levels (19), acceleration of nerve regeneration (20), and cardiac differentiation (21). Other studies presented evidence for ELF-EMF effects on protein phosphorylation (22,23) and on the activity of stress proteins (24) and kinases (25,26). In vivo studies demonstrated an increased level of apoptotic cells in mouse brain and liver (27).…”

Immunomodulating action of low intensity millimeter waves on primed neutrophils

“…Phosphorylation is one of the crucial steps in intracellular signaling in different cells, and it could be of importance in the intracellular mechanisms of the electromagnetic field effects [Jin et al, 2000]. Data on the effects of the low energy electromagnetic fields on phosphorylation and protein kinase activity are accumulating [Byus et al, 1984;Browning and Haycock, 1988;Dibirdik et al, 1998;Kristupaitis et al, 1998;Miller and Furniss, 1998;Tuinstra et al, 1998;Dibirdik et al, 2000;Woods et al, 2000;Wetzel et al, 2001].…”