Light in the red to near-infrared (NIR) range (630–1000 nm) generated by low energy laser or light-emitting diodes (LEDs) was reported to have beneficial biological effects in a range of injury models [1, 2]. Such photobiomodulation has been observed to increase the mitochondrial metabolism [36], facilitate wound healing [79], and promote angiogenesis in the skin [7], bone [10], nerve [11], and skeletal muscle [1215]. Red and NIR have beneficial effects on cells by “kick-starting” them into immediately creating more adenosine triphosphate (ATP) and increasing the DNA and RNA activity. This effect has been examined extensively since 1987. The positive effects were observed only in injured cells; no benefit was observed in healthy cells. Tissue repair and healing of injured skin are complex processes that involve a dynamic series of events including coagulation, inflammation, granulation tissue formation, wound contraction, and tissue remodeling [16]. The ideal wavelengths were reported to be between 600 and 900 nm with the best results obtained at specific ranges: 610–625, 660–690, 750–770, and 815–860 nm. NIR via LED is a well-accepted therapeutic tool in the treatment of infected, ischemic, and hypoxic wounds, as well as other soft tissue injuries in humans and animals [17, 18]. The mechanism of NIR-LED action is the upregulation of the cytochrome C oxidase activity and the production of ATP, as observed in primary cultures of rat visual cortical neurons inactivated functionally by tetrodotoxin, potassium cyanide (KCN), or sodium azide (N3Na) [19].

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