Translational Relevance
The effects of UV irradiation on tissue include a consecutive series of events starting with the absorption of the photons by chromophores in the skin (photoexcitation), followed by photochemical reactions, which induce molecular changes in cell and tissue biology and affect signaling networks. UV irradiation may cause both beneficial and damaging effects, which depend on wavelength, radiation exposure, and the UV source. Low-dose UVB exposure induces the production of vitamin D in the skin.5 Recently, studies have shown that irradiation of cultured cells with UV activates genes that influence cell division and immune responses.4,6 It is hypothesized that judicious UV exposure might be beneficial for wound healing and restoration of skin homeostasis besides its anti-inflammatory and antioxidant effects.6,7 UV light has been investigated as a potential modulator of keratinocyte–melanocyte cross talk in promoting wound healing.7