Low-frequency magnetic fields do not aggravate disease in mouse models of Alzheimer's disease and amyotrophic lateral sclerosis

Abstract

Low-frequency magnetic fields (LF-MF) generated by power lines represent a potential environmental health risk and are classified as possibly carcinogenic by the World Health Organization. Epidemiological studies indicate that LF-MF might propagate neurodegenerative diseases like Alzheimer's disease (AD) or amyotrophic lateral sclerosis (ALS). We conducted a comprehensive analysis to determine whether long-term exposure to LF-MF (50 Hz, 1 mT) interferes with disease development in established mouse models for AD and ALS, namely APP23 mice and mice expressing mutant Cu/Zn-superoxide dismutase (SOD1), respectively. Exposure for 16 months did not aggravate learning deficit of APP23 mice. Likewise, disease onset and survival of SOD1G85R or SOD1G93A mice were not altered upon LF-MF exposure for ten or eight months, respectively. These results and an extended biochemical analysis of protein aggregation, glial activation and levels of toxic protein species suggests that LF-MF do not affect cellular processes involved in the pathogenesis of AD or ALS.

Residential exposure to electromagnetic fields and risk of amyotrophic lateral sclerosis: a dose–response meta-analysis

“…An in vitro ALS model reported that magnetic field exposure caused impairment of iron homeostasis in SOD-1 mutant cells through deregulation of expression of iron-related genes, recently suggested as molecular determinant in the pathogenesis of ALS 46 . However, in mouse models expressing mutant Cu/Zn-superoxide dismutase, low-frequency magnetic field exposure did not alter disease onset and survival 47 . Another report implementing a SOD-1 transgenic mouse model did not reveal any effect on survival between exposed and unexposed groups.…”

Occupational exposure to extremely low frequency magnetic fields and risk of Alzheimer disease: A systematic review and meta-analysis

“…However, a recent report suggests that long-term exposure (18 months) to ELF-MF (50 Hz, 1 mT) has no effect on the cellular processes involved in the pathogenesis of AD (Liebl et al, 2015). Only few in vivo studies are available to support this theory; most recent studies such as Liebl et al (2016) (Liebl et al, 2015) (the first comprehensive study on the association of ELF-MF with AD in mouse models) or Maes et al (2016) (Maes et al, 2016) suggested that further investigations are needed. In general, experimental findings are based on short-term exposure to very high ELF-MF (typically ≥1 mT) and these studies do not represent realistic occupational exposure scenarios (long-term at lower levels).…”

“…The main theoretical premise behind this hypothesis is that exposure to ELF-MF can promote inflammation processes and thus influence the progression of neurodegenerative diseases including AD (Galasko and Montine, 2010;Grammas, 2011). However, a recent report suggests that long-term exposure (18 months) to ELF-MF (50 Hz, 1 mT) has no effect on the cellular processes involved in the pathogenesis of AD (Liebl et al, 2015). Only few in vivo studies are available to support this theory; most recent studies such as Liebl et al (2016) (Liebl et al, 2015) (the first comprehensive study on the association of ELF-MF with AD in mouse models) or Maes et al (2016) (Maes et al, 2016) suggested that further investigations are needed.…”

Microwave fields have little effect on α‐synuclein aggregation in a Caenorhabditis elegans model of Parkinson's disease

“…Similarly, 900 MHz GSM fields caused only modest increases in constitutive HSP70 and HSP90 expression and concomitantly decreased α‐synuclein expression, all of which were attributable to a 0.5 °C increase in temperature [Terro et al, ]. Recent reports using long‐term ELF EMF exposures suggest these did not aggravate disease in mouse models of Alzheimer's or amyotrophic lateral sclerosis [Liebl et al, ], and improved both spatial memory disorder and hippocampal damage in a rat model of Alzheimer's [Liu et al, ]. Further studies of EMF effects in tractable models of human neurodegenerative diseases are urgently needed, and any robust effects reported will require exact replication by several independent laboratories.…”