Extremely Low Frequency Magnetic Field (ELF-MF) Exposure Sensitizes SH-SY5Y Cells to the Pro-Parkinson’s Disease Toxin MPP

• Published in: Molecular neurobiology 2016-08, Vol.53 (6), p.4247-4260
• Main Authors: Benassi, Barbara, Filomeni, Giuseppe, Montagna, Costanza, Merla, Caterina, Lopresto, Vanni, Pinto, Rosanna, Marino, Carmela, Consales, Claudia
• Format: Article
• Language: English
• Subjects: 1-Methyl-4-phenylpyridinium - toxicity; Biomedical and Life Sciences; Biomedicine; Cell Biology; Cell Line, Tumor; Cell Proliferation - drug effects; Cell Shape - drug effects; Cell Survival - drug effects; Homeostasis - drug effects; Humans; Magnetic Fields; Neurobiology; Neurology; Neurosciences; Oxidation-Reduction - drug effects; Oxidative Stress - drug effects; Parkinson Disease - pathology; Protein Carbonylation - drug effects; Sulfhydryl Compounds - metabolism
• ISSN: 0893-7648; 1559-1182
• DOI: 10.1007/s12035-015-9354-4

Parkinson’s disease (PD) is a neurodegenerative disorder characterized by dopaminergic neuron loss, with an etiopathogenesis involving both genetic and environmental factors. The occupational/residential exposure to the electromagnetic fields has been recently associated with an increased risk of neurodegenerative diseases; it has been thus proposed that the extremely low frequency magnetic field (ELF-MF) may contribute to neurodegenerative etiopathogenesis, as its interaction with biological systems directly impairs redox homeostasis in specific areas of the brain. The molecular mechanisms elicited by ELF-MF, and their potential involvement in PD onset, still remain unclear. To this end, we set up a generator of ELF-MF able to stably and homogeneously reproduce environmental prolonged exposure to ELF-MF (50 Hz, 1 mT). Results obtained indicate that ELF-MF exposure alters cell response of SH-SY5Y cells to MPP + . We demonstrate that ELF-MF does not affect per se survival, shape, and morphology of both proliferating and differentiated SH-SY5Y cells but significantly impairs redox homeostasis and thiol content, triggering an increase in protein carbonylation. As a result, toxicity of MPP + , even at low doses, is highly enhanced in ELF-MF-exposed cells due to a significant increase in ROS levels, potentiation of oxidative damage, and induction of a caspase-dependent apoptosis. Pre-incubation with the thiol antioxidants N -acetyl- l -cysteine and GSH ethyl-ester significantly reduces the extent of oxidative damage and protects cells from death induced by the combined treatment ELF-MF/MPP + . Taken overall, our results demonstrate the redox-based molecular interaction between ELF-MF and PD neurotoxins in vitro, and open a new scenario for defining the synergy of environmental factors in PD onset.