Extremely Low-Frequency Electromagnetic Fields Promote In Vitro Neuronal Differentiation and Neurite Outgrowth of Embryonic Neural Stem Cells via Up-Regulating TRPC1

Abstract

Exposure to extremely low-frequency electromagnetic fields (ELF-EMFs) can enhance hippocampal neurogenesis in adult mice. However, little is focused on the effects of ELF-EMFs on embryonic neurogenesis. Here, we studied the potential effects of ELF-EMFs on embryonic neural stem cells (eNSCs). We exposed eNSCs to ELF-EMF (50 Hz, 1 mT) for 1, 2, and 3 days with 4 hours per day. We found that eNSC proliferation and maintenance were significantly enhanced after ELF-EMF exposure in proliferation medium. ELF-EMF exposure increased the ratio of differentiated neurons and promoted the neurite outgrowth of eNSC-derived neurons without influencing astrocyes differentiation and the cell apoptosis. In addition, the expression of the proneural genes, NeuroD and Ngn1, which are crucial for neuronal differentiation and neurite outgrowth, was increased after ELF-EMF exposure. Moreover, the expression of transient receptor potential canonical 1 (TRPC1) was significantly up-regulated accompanied by increased the peak amplitude of intracellular calcium level induced by ELF-EMF. Furthermore, silencing TRPC1 expression eliminated the up-regulation of the proneural genes and the promotion of neuronal differentiation and neurite outgrowth induced by ELF-EMF. These results suggest that ELF-EMF exposure promotes the neuronal differentiation and neurite outgrowth of eNSCs via up-regulation the expression of TRPC1 and proneural genes (NeuroD and Ngn1). These findings also provide new insights in understanding the effects of ELF-EMF exposure on embryonic brain development.

Effects of Fifty-Hertz Electromagnetic Fields on Granulocytic Differentiation of ATRA-Treated Acute Promyelocytic Leukemia NB4 Cells

“…The exposure to extremely low frequency ELF-EMF (50 Hz) induced more rapid maturation and differentiation in neural cells. These included rat immature cerebellar granule neurons and mouse embryonic neural stem cells [3, 41], as well as mouse pituitary corticotrope-derived cells [42]. Similar results were obtained in human cardiac stem cells derived from human myocardial bioptic specimens, where differentiation toward a cardiac-specific phenotype was observed after exposure to low-frequency EMF [43].…”

“…ELF-EMF is proven to affect differentiation in murine and human cells of different origins [3, 41-44]. The exposure to extremely low frequency ELF-EMF (50 Hz) induced more rapid maturation and differentiation in neural cells.…”

Biomaterials for Enhancing Neuronal Repair

“…Differentiation was attributed to the topography facilitating binding between cellular integrins and ligands, which (Xie et al, 2009;Schaub and Gilbert, 2011;Wong et al, 2011;Froeter et al, 2014;Koppes et al, 2014;Lee et al, 2015b). b Electrical References: (Jaffe and Stern, 1979;Patel and Poo, 1982;Hotary and Robinson, 1991;Davenport and McCaig, 1993;Metcalf and Borgens, 1994;Yao et al, 2008Yao et al, , 2009Yao et al, , 2011Graves et al, 2011;Koppes et al, 2014;Kim et al, 2016;Ma et al, 2016). c Mechanical Stiffness References: (Balgude et al, 2001;Discher et al, 2005;Jiang et al, 2010;Keung et al, 2012;Lee et al, 2013;Zhang et al, 2014;Mosley et al, 2017).…”

“…In early development, electric potentials define migration paths of the cells and differentiation, driving the formation of the neural tube Robinson, 1990, 1991;Metcalf and Borgens, 1994;Yao et al, 2008;Ma et al, 2016). Signal transmission in neurons is mediated by ion fluxes across the cell membrane.…”

Expression levels of PDYN and OPRM1 genes in SH-SY5Y cells exposed to 50 Hz electromagnetic field

“…19 It has been reported that ELF-EMF may alter the mRNA expression levels of several genes 20,21 including the brain, 22,23 neuroblastoma cells, 24 and embryonic neural stem cells. 25,26 As there is no study published yet about investigation on the alteration of the PDYN and OPRM1 mRNA expression levels in human SH-SY5Y cells due to ELF-EMF, we designed and carried out the following experiment.…”