Enhancing the Therapeutic Potential of Mesenchymal Stem Cells with Light-Emitting Diode: Implications and Molecular Mechanisms

Table 3

Main effects of LED irradiation on mesenchymal stem cells.

References	Viability	Proliferation	DNA damage	Differentiation	Metabolism	Secretome	Senescence	Scratch
[44]	NE	↑ Liu’s staining (multiple LED applications: 5 and 15 mW/cm^2; 2 and 4 J/cm^2); ↑CFU-F (multiple LED applications: 15 mW/cm^2; 4 J/cm^2)	NE	↑ Osteogenic (ALP activity; osteocalcin expression; (multiple LED applications: 15 mW/cm^2; 4 J/cm^2)	↑ ATP (single LED application: 15 mW/cm^2; 4 J/cm^2)	NE	NE	NE
[45]	NE	↑ BrdU	NE	NE	↑ Mitochondrial activity; ↑ ATP	↑ NO (nitrite)	NE	NE
[46]	NE	NE	NE	↑ Endothelial cells (CD31, CD34, and KDR); ↑ Epithelial cells (cytokeratin)	NE	↑ FGF, HGF and VEGF (6 J/cm^2)	NE	NE
[13]	NE	↑ WST-8 (1, 2 and 4 J/cm^2); ↑ EdU staining (2 J/cm^2)	NE	= Osteogenic (ALP activity; Alp1, Bglap, Col1α1, Runx2, and gene expression); = Mineral nodule formation (Von Kossa staining)	NE	NE	NE	NE
[47]	= Trypan blue	↑ WST-1 (0.954 J/cm^2); ↑ Hoechst staining; = CFU-F	NE	NE	NE	NE	NE	=
[48]	NE	NE	↑ Fragmented DNA (4 and 32 J/cm^2)	NE	═ Mitochondrial membrane potential	NE	═ β-Galactosidase staining	NE
[49]	NE	↑ Cell counts (2.4, 4.8, and 7.2 J/cm^2)	NE	NE	↑ ROS	↑ NO (nitrite) (4.8 and 7.2 J/cm^2)	NE	NE
[50]	NE	NE	NE	↑ Gametogenic (gene/protein expression: DAZL and SCP3)	NE	NE	NE	NE
[51]	NE	↑ WST-1 and ↑ CFU-F (7.12 mW/cm^2: 1 J/cm^2)	NE	= Adipogenic (red oil; gene expression: PPARγ, LPL); = Osteogenic (Alizarin red S; gene expression: ALP, Bglap)	↑ Mitochondrial activity (7.12 mW/cm^2: 1 J/cm^2)	↑ FGF and VEGF	↑ Self-renewal (genes: NANOG, OCT4 and SOX2; 7.12 mW/cm^2: 1 J/cm^2)	NE
[54]	NE	↓ MTT (1, 2, 4 and J/cm^2)	NE	↑ Osteogenic (ALP activity; gene expression: gene type I, osteocalcin and Runx2); ↑ Mineralization (Alizarin red oil)	NE	NE	NE	NE

NE: not evaluated; ↑: increase; ↓: reduction; =: not changed. ALP: alkaline phosphatase; ATP: adenosine 5´-triphosphate; Bglap: osteocalcin; BrdU: 5-bromo-2-deoxy-uridine; CFU-F: colony-forming unit fibroblasts; Col1α1: collagen type I; FGF: fibroblast growth factor; HGF: hepatocyte growth factor; LPL: lipoprotein lipase; MTT: 3-(4:5-dimethyl-2-thiazolyl)-2:5-diphenyl-2H-tetrazolium bromide; NANOG: nanog homeobox; NO: nitric oxide; PPARγ: peroxisome proliferator-activated receptor gamma; OCT4: octamer-binding transcription factor 4; ROS: reactive oxygen species (nonfluorescent marking 2:7-dichlorofluorescin diacetate); Runx2: runt-related transcription factor 2; SOX2: sex determining region Y-box; VEGF: vascular endothelial growth factor; WST-8: water-soluble tetrazolium.