Medical/biological study (experimental study)

S1P mediates human amniotic cells proliferation induced by a 50-Hz magnetic field exposure via ERK1/2 signaling pathway med./bio.

By: Qiu L, Chen L, Yang X, Ye A, Jiang W, Sun W

Published in: J Cell Physiol 2019; 234 (6): 7734-7741

Aim of study (acc. to author)

The possible role of sphingosine‐1‐phosphate in 50‐Hz magnetic field‐induced cell proliferation of human amniotic cells should be investigated.

Background/further details

Cells were either exposed or sham exposed. In some tests, cells were tested under addition of SKI II, an inhibitor of sphingosine kinase, or U0126, an inhibitor of ERK 1 and 2.

Endpoint

cell viability/cell division/proliferation: cell proliferation and underlying mechanism of action

Exposure

- 50/60 Hz
- magnetic field

Exposure	Parameters
Exposure 1: 50 Hz Exposure duration: 60 min	magnetic flux density: 0.4 mT

Exposure 1

Main characteristics

Frequency	50 Hz
Type	magnetic field
Waveform	sinusoidal
Exposure duration	60 min

Exposure setup

Exposure source	Helmholtz coils
Chamber	two exposure chambers which were put in a CO₂ incubator
Setup	one chamber was used for exposure and the other for sham exposure; each chamber consisted of a set of square Helmholtz coils (20 × 20 cm²), which was encased by mu‐metal for shielding the cells placed in the coils from stray magnetic fields; a fan on the metal wall ensured the air and the temperature was uniform between inside the chamber and incubator; during exposure, cell dishes were put in the center of the chambers; the temperature in the chambers was kept at 37.0 ± 0.2°C throughout the whole exposure period; the difference of the temperature between exposure and sham exposure conditions during the entire exposure period did not exceed 0.1°C
Sham exposure	A sham exposure was conducted.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	0.4 mT	-	-	-	-

Reference articles

Feng B et al. (2016): Mitochondrial ROS Release and Subsequent Akt Activation Potentially Mediated the Anti-Apoptotic Effect of a 50-Hz Magnetic Field on FL Cells
Qiu L et al. (2016): Exposure to a 50-Hz magnetic field induced ceramide generation in cultured cells
Schuderer J et al. (2004): In vitro exposure apparatus for ELF magnetic fields

Exposed system:

intact cell/cell culture
human amniotic (FL) cells

Methods Endpoint/measurement parameters/methodology

cell viability/cell division/proliferation: cell proliferation and cell viability (spectrophotometric plate reader)
molecular biosynthesis: level of lipids (ceramides, sphingosine and sphingosine‐1‐phosphate) in cell extracts (HPLC-tandem mass spectrometry), protein expression of (phosphorylated) ERK 1/2 (Western blot)

Investigated system:

intact cell/cell culture
isolated bio./chem. substance
cell extracts

Time of investigation:

after exposure

Main outcome of study (acc. to author)

Exposure to the magnetic field increased cell proliferation, enhanced levels of ceramides and sphingosin-1-phosphate and activated ERK 1/2 significantly compared to the sham exposure.
The increase in cell proliferation and ERK1/2 activation was inhibited by the sphingosine kinase inhibitor SKI II and the inhibitor of ERK 1 and 2, U0126.
The authors conclude that sphingosine‐1‐phosphate could mediate 50‐Hz magnetic field‐induced cell proliferation of human amniotic cells via triggering the ERK1/2 signal pathway.

Study character:

medical/biological study
experimental study
full/main study
blind study

Study funded by

National Natural Science Foundation (NSFC), China

Martínez MA et al. (2021): Role of NADPH oxidase in MAPK signaling activation by a 50 Hz magnetic field in human neuroblastoma cells
Yang X et al. (2019): Involvement of calcium in 50-Hz magnetic field-induced activation of sphingosine kinase 1 signaling pathway
Martínez MA et al. (2019): Involvement of the EGF Receptor in MAPK Signaling Activation by a 50 Hz Magnetic Field in Human Neuroblastoma Cells
Kapri-Pardes E et al. (2017): Activation of Signaling Cascades by Weak Extremely Low Frequency Electromagnetic Fields
Qiu L et al. (2016): Exposure to a 50-Hz magnetic field induced ceramide generation in cultured cells
Martinez MA et al. (2016): Power Frequency Magnetic Fields Affect the p38 MAPK-Mediated Regulation of NB69 Cell Proliferation Implication of Free Radicals
Xu H et al. (2016): Low frequency pulsed electromagnetic field promotes C2C12 myoblasts proliferation via activation of MAPK/ERK pathway
Patruno A et al. (2015): mTOR Activation by PI3K/Akt and ERK Signaling in Short ELF-EMF Exposed Human Keratinocytes
Martinez MA et al. (2012): The Proliferative Response of NB69 Human Neuroblastoma Cells to a 50 Hz Magnetic Field is mediated by ERK1/2 Signaling
Goodman R et al. (2009): Extremely low frequency electromagnetic fields activate the ERK cascade, increase hsp70 protein levels and promote regeneration in Planaria
Nie K et al. (2003): MAP kinase activation in cells exposed to a 60 Hz electromagnetic field