Medical/biological study (experimental study)

Pulsed electromagnetic field stimulation of MG63 osteoblast-like cells affects differentiation and local factor production med./bio.

By: Lohmann CH, Schwartz Z, Liu Y, Guerkov H, Dean DD, Simon B, Boyan BD

Published in: J Orthop Res 2000; 18 (4): 637-646

Aim of study (acc. to author)

To examine the response of osteoblast-like cells to a pulsed electromagnetic field signal used clinically and to determine if the signal modulates the production of autocrine factors associated with differentiation.

Endpoint

molecular biosynthesis: production of autocrine factors
cell function: cell differentiation

Exposure

- magnetic field
- low frequency
- signals/pulses

Exposure	Parameters
Exposure 1: 15 Hz Modulation type: pulsed Exposure duration: 8 h/d for 1, 2 or 4 days	magnetic flux density: 1.8 mT effective value (increased from 0 T to 1.8 mT within 200 µs and decayed back to 0 T in 25 µs.)

Exposure 1

Main characteristics

Frequency	15 Hz
Type	magnetic field
Waveform	pulsed
Exposure duration	8 h/d for 1, 2 or 4 days

Modulation

Modulation type	pulsed
Rise time	200 µs
Fall time	25 µs
Additional info	5 ms bursts of 20 pulses

Exposure setup

Exposure source	Helmholtz coils
Chamber	Incubator with Plexiglas shelves.
Setup	Culture placed between Helmholtz coils

Parameters

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	1.8 mT	effective value	unspecified	-	increased from 0 T to 1.8 mT within 200 µs and decayed back to 0 T in 25 µs.

Additional parameter details

Background fields were less than 0.1 µT rms in the incubators and were less than 0.4 µT rms when the heater and water circulator were on.

Exposed system:

intact cell/cell culture
MG63 (osteoblast-like cells)

Methods Endpoint/measurement parameters/methodology

molecular biosynthesis: level of osteocalcin, prostaglandin E₂, and transforming growth factor (TGF)-β1; matrix protein synthesis
cell function: cell differentiation (alkaline phosphatase specific activity)
cell viability/cell division/proliferation: cell proliferation (cell number; [³H]thymidine incorporation)

Investigated system:

isolated bio./chem. substance
intact cell/cell culture
lysates of isolated cells or cell layers

Time of investigation:

after exposure

Main outcome of study (acc. to author)

The results show that pulsed electromagnetic field stimulation affects the proliferation, differentiation, extracellular matrix synthesis, and local factor production of MG63 cells. Exposed cells exhibited a more differentiated phenotype, as evidenced by reduced cell proliferation and increased alkaline phosphatase activity. Pulsed electromagnetic field stimulation affected osteocalcin production, increases TGF-β1 levels and inhibits the synthesis of prostaglandin E₂. Cell number and [³H]thymidine incorporation were reduced.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

B.Braun Foundation, Melsungen, Germany
Center for the Enhancement of the Biology/Biomaterials Interface (CEBBI; at the University of Texas Health Science Center), San Antonio, Texas
Electro-Biology, Parsippany, New York, USA

Bique AM et al. (2016): Choice of osteoblast model critical for studying the effects of electromagnetic stimulation on osteogenesis in vitro
Barnaba SA et al. (2012): Clinical significance of different effects of static and pulsed electromagnetic fields on human osteoclast cultures
Celik MS et al. (2012): The effects of long-term exposure to extremely low-frequency magnetic fields on bone formation in ovariectomized rats
Sun LY et al. (2009): Effect of pulsed electromagnetic field on the proliferation and differentiation potential of human bone marrow mesenchymal stem cells
Zhao D et al. (2008): Electromagnetic field change the expression of osteogenesis genes in murine bone marrow mesenchymal stem cells
Sul AR et al. (2006): Effects of sinusoidal electromagnetic field on structure and function of different kinds of cell lines