Study type: Medical/biological study (experimental study)

ELF-MF transiently increases skeletal myoblast migration: possible role of calpain system med./bio.

Published in: Int J Radiat Biol 2013; 89 (7): 548-561

Aim of study (acc. to author)

To study whether extremely low frequency magnetic fields could affect myoblast migration (an essential step in myogenesis).

Background/further details

As Ca2+-dependent calpains contribute to the regulation of myoblast motility the effect of magnetic field exposure on µ-calpain and m-calpain was also investigated.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 50 Hz
Exposure duration: continuous for up to 24 h (30 min, 2 h, 6 h, 12 h, 18 h, 24 h)

Exposure 1

Main characteristics
Frequency 50 Hz
Type
Waveform
Exposure duration continuous for up to 24 h (30 min, 2 h, 6 h, 12 h, 18 h, 24 h)
Exposure setup
Exposure source
Setup pair of Helmholtz coils with a radius of 13 cm ± 0,5 cm and 800 turns of wire, placed vertically at a distance of 13.5 cm ± 0.5 cm; stack of 5 culture plates exposed simultaneously; field uniformity better than 1% in the exposure area in the center of the coil system; exposure system placed in an incubator; two identical exposure systems, one for sham exposure and one for real exposure, used in a random fashion
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 1 mT - - - -

Reference articles

  • Kirschvink JL (1992): Uniform magnetic fields and double-wrapped coil systems: improved techniques for the design of bioelectromagnetic experiments

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Time of investigation:
  • after exposure

Main outcome of study (acc. to author)

Exposure to extremely low frequency magnetic fields resulted in a transient, but significant increase of myoblast migration at 6 h of exposure. This effect was associated with a marked increase of µ- and m-calpain enzyme activity (at 2 h and 6 h of exposure, respectively) followed by the concomitant variation in their subcellular localization. No significant changes in intracellular distribution and protein levels of calpastatin were found. Finally, a significant decrease of MARCKS protein expression (at 2 h and 6 h of exposure) and modifications of actin dynamics were observed.
The data showed an involvement of calpains in extremely low frequency magnetic field-mediated myoblast migration.

Study character:

Study funded by

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