Direct and Indirect Effects of Blue Light Exposure on Skin: A Review of Published Literature

Abstract

The growing use of electronic devices and other artificial light sources in recent decades has changed the pattern of exposure to blue light (400–500 nm). Although some progress has been made in the study of the biological effects of blue light on the skin, many questions in this field remain unexplored. The aim of this article was to review the currently available evidence on the deleterious effects of blue light on the skin, as well as the methods and strategies designed to protect from the detrimental effects of blue light. PubMed and ProQuest databases were searched in January 2022. Search results were supplemented by articles considered relevant by the authors. The results of in vitro, in vivo and clinical studies show that blue light produces direct and indirect effects on the skin. The most significant direct effects are the excessive generation of reactive oxygen and nitrogen species, and hyperpigmentation. Reactive oxygen and nitrogen species cause DNA damage and modulate the immune response. Indirect effects of blue light include disruption of the central circadian rhythm regulation via melatonin signaling and local circadian rhythm regulation via direct effects on skin cells. Antioxidants and sunscreens containing titanium dioxide, iron oxides, and zinc oxide can be used to protect against the detrimental effects of blue light as part of a strategy that combines daytime protection and night-time repair. Blue light produces a wide variety of direct and indirect effects on the skin. As exposure to blue light from artificial sources is likely to continue to increase, this area warrants further investigation.

Differential Photosensitivity of Fibroblasts Obtained from Normal Skin and Hypertrophic Scar Tissues

“…Whether BL is harmful to skin cells is controversial [47]. The dose of BL used in our study was lower than that used in many reports.…”

Oxygen-confined photooxidation represents a novel form of oxidative protein damage

“…This oxidation pathway could potentially contribute to photodamage in tissues that are directly exposed to visible light, such as skin and eyes. It has been reported that the blue light irradiation can lead to tissue aging and disorders, including the visible-light penetrating tissues [49][50][51][52][53][54] . The photodamage effects are suggested to result from elevated oxidative stress caused by blue light-induced ROS generation through endogenous photosensitizers 49,[55][56][57][58][59] .…”

“…It has been reported that the blue light irradiation can lead to tissue aging and disorders, including the visible-light penetrating tissues [49][50][51][52][53][54] . The photodamage effects are suggested to result from elevated oxidative stress caused by blue light-induced ROS generation through endogenous photosensitizers 49,[55][56][57][58][59] . The photooxidation we report here may represent a hidden pathway within oxidative damage networks, contributing to overall protein damage in the skin and eyes.…”

Standards for Quantitative Measurement of DNA Damage in Mammalian Cells

“…A practical form of radiation treatment is the exposure of cultured mammalian cells to near-ultra-violet light (UVA, 315 nm < l < 400 nm) and visible light [ 62 ] in the presence of photosensitizers [ 63 ] at doses ranging from 0 to 5 J/cm 2 . Visible spectrum photosensitizers such as Ro 19 8022 are widely used for base oxidation; however, their efficiency in producing strand brakes is limited [ 64 ]. To produce measurable DNA double-strand breaks that are detectable by a γ- H2AX assay, CHO cells require pre-exposure with the catalyst benzo [a] pyrene (BaP) at concentrations ranging from 10 −9 mol/L to 10 −7 mol/L [ 65 ].…”