Physical energies to the rescue of damaged tissues

Table 3 Photobiomodulation studies

Photobiomodulation	Conditions	Biological effects	References number
LLLT	Tumor transplantation in rats	Failure to affect the implanted tumor; Stimulation of hair regrowth and wound healing	[135-138]
Cell-generated electromagnetic (light) signals	Baby hamster kidney cells on thin glass film	Cell migration and orientation afforded by endogenous generation and processing of signals carried out by electromagnetic radiation (light)	[139]
Near-infrared light scattering	Cell culture	Near-infrared light scattering by cells mediates long-range attraction between them and aggregation within the culture system	[140]
PBM with blue (420 nm) or green (540 nm) light	hADSCs	Promotion of osteoblastic differentiation; Overexpression of a gene program of osteogenesis; Increase of intracellular calcium mediated by the activation of light-gated calcium ion channels	[141, 142]
PBM with red (660 nm) or near-infrared (810 nm) light	hADSCs	Induction of cell proliferation; Maintenance of low ROS level	[151]
PBM with blue (415 nm) or green (540 nm) light	hADSCs	Inhibition of cell proliferation; Increase of low ROS level; Lowering of mitochondrial membrane potential and intracellular pH	[151]
Various forms of PBM	Acute stroke in animal models	Improvement of the outcome of acute stroke	[152-157]
PBM with 810 nm laser light	Human moderate-to-severe stroke associated with neurological defects	Long-lasting neurological improvement	[158-160]
Near-infrared light scattering (665 nm and 810 nm)	Traumatic brain injury in animal models	Rescue of neurological performance and reduction of the size of brain lesions; Increase of neuroprogenitor cells in mouse dentate gyrus and subventricular zone; Increase of learning memory; Improvement of mitochondrial function	[161-168]
Near-infrared light scattering (665 nm and 810 nm)	Human traumatic brain injury	Improvement of both language and cognitive performance, as well as brain tissue recovery	[169-171]
PBM with near-infrared (810 nm) light	Alzheimer’s disease in animal models	Reduction of amyloid beta plaques; Decrease in the expression of pro-inflammatory cytokines; Increase in mitochondrial function, and ATP levels	[172]
PBM with near-infrared (810 nm) light	Human Alzheimer’s disease	Improvement in Alzheimer's Disease Assessment Scale - Cognitive assessment; Enhancement of cerebral microcirculation	[173-174]
PBM with near-infrared (810 nm) light	Parkinson’s disease in animal models	Increase in the number of dopaminergic neurons	[175-176]
PBM with near-infrared (810 nm) light	Human Parkinson’s disease	Improvement of the investigated indicators of balance, including gait, cognitive function, and speech	[177]
LLLT	Acute Myocardial infarction in the pig	Reduction of scarring; Improvement of heart function; Stem cell mobilization and recruitment to the ischemic heart	[178]

LLLT: Low level light therapy; hADSCs: Human adipose tissue-derived stem cells; PBM: Photobiomodulation.