Combined effects of electromagnetic field and low-level laser increase proliferation and alter the morphology of human adipose tissue-derived mesenchymal stem cells

Abstract

In recent years, electromagnetic field (EMF) and low-level laser (LLL) have been found to affect various biological processes, the growth and proliferation of cells, and especially that of stem cells. The aim of this study was to investigate the effects of EMF and LLL on proliferation of human adipose tissue-derived mesenchymal stem cells (hAT-MSCs) and thus to examine the impact of these therapeutic physical modalities on stem cell engraftment. hAT-MSCs were isolated from subcutaneous adipose tissue of six persons ranging in age from 21 to 56 years. EMF was applied for a period of 7 days, once a day for 30 min, via a magnetic cushion surface at a frequency of 50 Hz and an intensity of 3 mT. LLL was applied also for 7 days, once a day for 5 min, at radiation energies of 3 J/cm, with a wavelength of 808 nm, power output of 200 mW, and power density of 0.2 W/cm. Nonexposed cells (control) were cultivated under the same culture conditions. Seven days after treatment, the cells were examined for cell viability, proliferation, and morphology. We found that after 7 days, the number of EMF-treated hAT-MSCs was significantly higher than the number of the untreated cells, LLL-treated hAT-MSCs were more numerous than EMF-treated cells, and hAT-MSCs that were treated with the combination of EMF and LLL were the most numerous. EMF and/or LLL treatment did not significantly affect hAT-MSC viability by itself. Changes in cell morphology were also observed, in terms of an increase in cell surface area and fractal dimension in hAT-MSCs treated with EMF and the combination of EMF and LLL. In conclusion, EMF and/or LLL treatment accelerated the proliferation of hAT-MSCs without compromising their viability, and therefore, they may be used in stem cell tissue engineering.

Effect of Photobiomodulation Therapy on the Increase of Viability and Proliferation of Human Mesenchymal Stem Cells

“…Khandra et al [33] showed there was increased cellular attachment, proliferation, differentiation, osteocalcin synthesis, and transforming growth factor β1 production in human osteoblast-like cells after low level laser irradiation. Nurković et al [21] demonstrated that PBMT accelerates MSC proliferation [21]. The results obtained were confirmed by the Gianellis team [34].…”

“…De Freitas and Hamblin consider that MSCs are particularly sensitive to low power laser irradiation, which causes increased gene expression, increased cell migration and proliferation, and accelerated production of antioxidant enzymes and anti‐apoptotic proteins. Nurkowić et al showed that after application of an electromagnetic field (EMF) (time, 30 min; frequency ‐50 Hz, intensity ‐3 mT for 7 days) and low level laser therapy (time, 5 min; energy density, 3 J/cm 2 ; wavelength, 808 nm; power density, 200 mW/cm 2 for 7 days) there were more MSCs than in untreated samples, with the biggest increase resulting from concurrent application of EMF and PBMT . Gianelli et al indicated that laser irradiation (power, 0.89 W; wavelength, 635 nm; continuous emission) stimulates MSC proliferation associated with increased membrane conductance.…”

“…De Freitas and Hamblin [55] consider that MSCs are particularly sensitive to low power laser irradiation, which causes increased gene expression, increased cell migration and proliferation, and accelerated production of antioxidant enzymes and antiapoptotic proteins. Nurkowić et al [21] showed that after application of an electromagnetic field (EMF) (time, 30 min; frequency -50 Hz, intensity -3 mT for 7 days) and low level laser therapy (time, 5 min; energy density, 3 J/cm 2 ; wavelength, 808 nm; power density, 200 mW/cm 2 Fig. 4.…”

“…MSCs can migrate from the bone marrow or peripheral blood to injured tissue due to metalloproteinases, proteolytic enzymes that allow them to traverse the extracellular matrix [16][17][18][19]. MSC differentiation, proliferation, directional mobility and many other processes can be activated by such factors such as the light-emitting diode (LED) and photobiomodulation therapy (PBMT), electromagnetic fields, and ultraviolet irradiation [20][21][22][23][24].…”

Low power laser irradiation and human adipose-derived stem cell treatments promote bone regeneration of critical-sized calvarial defects in rats

“…The biostimulating effects of this technique are achieved when a specific wavelength of light is absorbed by the photoreceptors of the irradiated cells [14]. A wide network of intracellular signaling cascades are then triggered, leading to various biological effects in promoting cell growth and survival, proliferation, collagen synthesis, and differentiation [15][16][17][18]. Studies have reported that LPLI exerts biostimulating effects on osteogenic cells and bone tissues in vitro [15,[19][20][21][22].…”