Study type: Medical/biological study (experimental study)

Effects of extremely low frequency electromagnetic fields on human fetal scleral fibroblasts. med./bio.

Published in: Toxicol Ind Health 2016; 32 (6): 1042-1051

Aim of study (acc. to author)

To investigate the effects of extremely low frequency magnetic fields on cell growth and factors involved in scleral structuring in scleral fibroblasts.

Background/further details

The possible impact of extremely low frequency magnetic fields on pathological alterations in the sclera has been rarely documented. However, it might play an important role in treating certain eye ailments (e.g. myopia) and therefore more research is required.
The sclera is a part of the human eye ("white of the eye"), mainly composed of collagen fibrils. Several factors can influence the correct formation and structure of these collagen fibrils. Therefore, the expression of several genes related to the collagen synthesis was examined.
The cells were exposed to a magnetic flux densitiy of 0.2 mT for 24 hours if not stated otherwise.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 50 Hz
Exposure duration: continuous for 24 hours
Exposure 2: 50 Hz
Exposure duration: continuous for 24 hours
gene expression experiment 1
Exposure 3: 50 Hz
Exposure duration: continuous for up to 48 hours (6, 12, 24, 36 or 48 hours)
gene expression experiment 2

Exposure 1

Main characteristics
Frequency 50 Hz
Type
Waveform
Exposure duration continuous for 24 hours
Additional info cell proliferation, protein expression, cell morphology
Exposure setup
Exposure source
Setup two exposure facilities (one for exposure, the other for sham exposure) with the same environment were put into two thermo-regulated and atmosphere-controlled incubators at 37°C and 5% CO2; the coils were 16 cm long, 14 cm wide and 8 cm high and consisted of 168 turns copper wire, respectively
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 0.2 mT - measured - -

Exposure 2

Main characteristics
Frequency 50 Hz
Type
Waveform
Exposure duration continuous for 24 hours
Additional info gene expression experiment 1
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 0.1 mT - measured - -
magnetic flux density 0.2 mT - measured - -
magnetic flux density 0.5 mT - measured - -
magnetic flux density 1 mT - measured - -

Exposure 3

Main characteristics
Frequency 50 Hz
Type
Waveform
Exposure duration continuous for up to 48 hours (6, 12, 24, 36 or 48 hours)
Additional info gene expression experiment 2
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 0.2 mT - measured - -

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Time of investigation:
  • after exposure

Main outcome of study (acc. to author)

The cell proliferation of exposed cells was significantly decreased compared to the control group. Additionally, the morphology of exposed cells differed from those of the control group: While untreated cells appeared fibroblast-like (spindle or bundle shape), the alignment of exposed cells was altered into irregular polygonal configurations.
The gene expression of collagen 1 (starting after 6 hours) and fibroblast growth factor-2 (starting after 12 hours) was significantly decreased after exposure to 0.2 mT and higher magnetic flux densities in comparison to the control, while the gene expression of matrix-metalloproteinase-2 (starting after 24 hours; 0.1 and 0.2 mT) and transforming growth factor beta-2 (starting after 24 hours; 0.5 mT and 1 mT) was significantly increased. However, the gene expression level of the matrix-metalloproteinase-2 inhibitor was significantly increased only after exposure to 1 mT compared to the control.
The protein expression analysis was in agreement with the results of the gene expression examination: In exposed cells, the protein expression of collagen 1 was significantly decreased compared to the control while the protein expression of matrix-metalloproteinase-2 was significantly increased.
The authors conclude that extremely low frequency magnetic fields could influence the growth of scleral fibroblasts as well as its gene expression and protein expression related to the structure of the sclera.

Study character:

Study funded by

Related articles