Effect of photobiomodulation on neural differentiation of human umbilical cord mesenchymal stem cells

Abstract

Photobiomodulation therapy (PBMT) can enhance the mesenchymal stem cell (MSC) proliferation, differentiation, and tissue repair and can therefore be used in regenerative medicine. The objective of this study is to investigate the effects of photobiomodulation on the directional neural differentiation of human umbilical cord mesenchymal stem cells (hUC-MSCs) and provide a theoretical basis for neurogenesis. hUC-MSCs were divided into control, inducer, laser, and lasers combined with inducer groups. A 635-nm laser and an 808-nm laser delivering energy densities from 0 to 10 J/cm were used in the study. Normal cerebrospinal fluid (CSF) and injured cerebrospinal fluid (iCSF) were used as inducers. The groups were continuously induced for 3 days. Cellular proliferation was evaluated using MTT. The marker proteins nestin (marker protein of the neural precursor cells), NeuN (marker protein of neuron), and GFAP (glial fibrillary acidic protein, marker proteins of glial cells) were detected by immunofluorescence and western blot. We found that irradiation with 635-nm laser increased cell proliferation, and that with 808 nm laser by itself and combined with cerebrospinal fluid treatment generated significant neuron-like morphological changes in the cells at 72 h. Nestin showed high positive expression at 24 h in the 808 nm group. The expression of GFAP increased in the 808-nm combined inducer group at 24 h but decreased at 72 h. The expression of neuN protein increased only at 72 h in both the 808-nm combined inducer group and inducer group. We concluded that 808 nm laser irradiation could help CSF to induce neuronal differentiation of hUC-MSCs in early stage and tend to change to neuron rather than glial cells.

The Effect of Photobiomodulation Therapy on the Differentiation, Proliferation, and Migration of the Mesenchymal Stem Cell: A Review

“…In order to investigate mitochondrial activity in the MSCs, it has been shown that the intensity mean of rhodamin123 fluorescence increases significantly compared to the laser-free MSCs. 23,25 Angiogenic properties increase significantly in the underlying laser MSCs by increasing the expression of angiogenesis-related genes (VEGF, PDGF, HGF, BFGF, ANGPT1, ANGPT2, SDF-a1), which can damage endothelial cells and can significantly increase total tube length and branch point compared to the laser-free MSCs. The study showed that low-level laser irradiation could increase angiogenesis by the inhibition of apoptosis in the mesenchymal stem.…”

“…The study also found that only an 808 nm laser could express the NeuN marker protein of neurons in 72 hours and a 635 nm laser increased the proliferation of the mesenchymal cells. 25 A laser with a wavelength of 635nm amplified the umbilical cord mesenchymal cells if it proved that a low-power laser with 808nm failed to increase the proliferation of the same cells. 26 Adipose Mesenchymal Stem Cells It has been reported that the toxic effects of doxorubicin on the adipose mesenchymal stem cells can be reduced by using a low-power laser with a wavelength of 660 nm, output power of 30 mW, a laser beam of 0.028 cm 2 , and irradiation of 1.07 mW/cm 2 .…”

Effects of photobiomodulation combined with MSCs transplantation on the repair of spinal cord injury in rat

“…Because of the continuous laser treatment, combined therapy can reduce the influence of adverse factors, including inflammation and edema. Furthermore, in previous studies, it was shown that laser irradiation significantly improved the activity of stem cells and improve the viability of cells (H. Chen et al, 2019), and that surviving hUCMSCs secreted neurotrophic factors and improved the microenvironment, thereby indicating the effect of combined therapy is obvious.…”

“…The hUCMSCs were provided by Tianjin Angsai Cell Genetic Engineering Co. Ltd., and were cultured and identified as described previously (H. Chen et al, 2019). Briefly, the cells were seeded in α‐MEN containing 10% fetal bovine serum, 0.05 U/ml penicillin and 0.05 μg/ml streptomycin, and cultured at 37°C under 5% CO 2 till the cells were 80–90% confluent.…”

“…Because of the continuous laser treatment, combined therapy can reduce the influence of adverse factors, including inflammation and edema. Furthermore, in previous studies, it was shown that laser irradiation significantly improved the activity of stem cells and improve the viability of cells(H. Chen et al, 2019), and that surviving hUCMSCs secreted neurotrophic factors and improved the microenvironment, thereby indicating the effect of combined therapy is obvious.Inflammation has been considered to play an important role in the pathophysiology of SCI. The neuro-inflammatory environment promotes the activation of macrophages/microglia, macrophages migrate to the injured site within minutes after injury, inflammatory cell infiltration causes significant neuronal death, and demyelinating lesions and syringomyelia occur at the injured site(Jones & Ren, 2016;Snyder & Yang, 2012;Yu & He, 2015).…”