Elevation of heat shock gene expression from static magnetic field exposure in vitro

Abstract

Previously, we found that extremely low frequency (ELF) electric fields were able to elicit an approximate 3.5-fold increase in heat shock gene expression, a response which may have applicability to cancer therapy. Based on recent studies demonstrating the ability of magnetic fields to influence gene expression, we hypothesized that low level static magnetic fields may be able to affect heat shock gene expression while avoiding some of the clinical difficulties that arise with electric fields. Transfected rat primary cells in monolayer were exposed to magnetic fields of 1 to 440 mT for 16, 24, or 48 h starting at 24 and 48 h post transfection. Heat shock protein (HSP70) expression, as indicated by a promoter linked luciferase reporter, was followed for up to 96 h and showed a dependence on flux density, exposure duration, and start time post transfection. A nonlinear response was observed for increasing flux density with a maximum of a 3.5-fold increase in expression for 48 h of exposure starting 48 h after transfection. These results demonstrate an enhancement of gene expression similar in magnitude to that observed with external electric field exposure, while eliminating many of the clinical complications.

Effect of static magnetic fields and phloretin on antioxidant defense system of human fibroblasts

“…In the report of Ghodbane et al ( 2011 ), however, compact electromagnets were applied. The results of Laramee et al ( 2014 ) also demonstrated that the response to SMFs was dependent on experimental variables. These authors suggested that only longer exposure durations (12–48 h) demonstrate some significant response to SMF.…”

“…Static magnetic fields can influence the expression of specific genes on human and other mammalian cells, and the effects may depend on the duration of exposure and the magnetic flux density. The results of Laramee et al ( 2014 ) revealed that the expression of heat shock protein ( HSP70 ) in primary rat fibroblasts increased after the exposure to MFs of 1 to 440 mT. Heat shock proteins are a group of functionally related molecular chaperones that can be used as markers for cellular stress (Sõti et al 2003 ).…”

Exposure to extremely low frequency electromagnetic fields alters the behaviour, physiology and stress protein levels of desert locusts

“…This could potentially link with the results from other parts of this study as a molecular signal of the physiological effects that could lead to modified behaviour. There is also evidence from studies on rats51 that extremely high levels of static EMF can also lead to an increased HSP70 expression, however these levels of static EMF are many orders of magnitude greater than geomagnetic fields normally encountered in the environment and which many insects can detect567.…”

Lack of effects on key cellular parameters of MRC-5 human lung fibroblasts exposed to 370 mT static magnetic field

“…In very recent literature, great attention has been devoted to study the effects on selected cellular endpoints related to cancer development, in different cell models. Gene expression and genotoxicity 15 16 17 18 19 20 , oxidative stress 21 22 23 24 , cell growth, differentiation and viability 16 22 25 26 27 28 29 have been investigated. In a consistent portion of the available studies, SMF exposure induced effects in the cellular endpoints that, in some cases, were transient.…”