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Blue light is an identified risk factor for age-related macular degeneration (AMD). The production of vascular endothelial growth factor (VEGF), leading to neovascularization, is a major complication of the wet form of this disease. We investigated how blue light affects VEGF expression and secretion using A2E-loaded retinal pigment epithelium (RPE) cells, a cell model of AMD. Incubation of RPE cells with A2E resulted in a significant increase in VEGF mRNA and, intracellular and secreted VEGF protein levels, but not mRNA levels of VEGFR1 or VEGFR2. Blue light exposure of A2E-loaded RPE cells resulted in a decrease in VEGF mRNA and protein levels, but an increase in VEGFR1 levels. The toxicity of 440 nm light on A2E-loaded RPE cells was enhanced by VEGF supplementation. Our results suggest that age-related A2E accumulation may result in VEGF synthesis and release. This synthesis of VEGF, which enhances blue light toxicity for the RPE cells, is itself suppressed by blue light. Anti-VEGF therapy may therefore improve RPE survival in AMD., Competing Interests: I have read the journal's policy and the authors of this manuscript have the following competing interests: CB and TV are Essilor employees. SP received fees for participating in a meeting organized by Essilor. SP received a grant from Essilor to work on light toxicity on retinal cells. No competing financial interests exist for PG, and DP. This does not alter our adherence to PLOS ONE policies on sharing data and materials. The authors would like to declare the following patents/patent applications associated with this research: EP2602655 : filtre ophtalmique; EP2602654 : filtre ophtalmique; EP2602653 : Méthode de la détermination de la configuration d'un filtre ophtalmique; EP19305328 : filter for eye cone cells protection.

Aims: Blue light is an identified risk factor for age-related macular degeneration (AMD). We investigated oxidative stress markers and mitochondrial changes in A2E-loaded retinal pigment epithelium cells under the blue-green part of the solar spectrum that reaches the retina to better understand the mechanisms underlying light-elicited toxicity., Results: Primary retinal pigment epithelium cells were loaded with a retinal photosensitizer, AE2, to mimic aging. Using a custom-made illumination device that delivers 10 nm-wide light bands, we demonstrated that A2E-loaded RPE cells generated high levels of both hydrogen peroxide (H 2 O 2 ) and superoxide anion (O 2 ) when exposed to blue-violet light. In addition, they exhibited perinuclear clustering of mitochondria with a decrease of both their mitochondrial membrane potential and their respiratory activities. The increase of oxidative stress resulted in increased levels of the oxidized form of glutathione and decreased superoxide dismutase (SOD) and catalase activities. Furthermore, mRNA expression levels of the main antioxidant enzymes (SOD2, catalase, and GPX1) also decreased.•- ) when exposed to blue-violet light. In addition, they exhibited perinuclear clustering of mitochondria with a decrease of both their mitochondrial membrane potential and their respiratory activities. The increase of oxidative stress resulted in increased levels of the oxidized form of glutathione and decreased superoxide dismutase (SOD) and catalase activities. Furthermore, mRNA expression levels of the main antioxidant enzymes (SOD2, catalase, and GPX1) also decreased., Conclusions: Using an innovative illumination device, we measured the precise action spectrum of the oxidative stress mechanisms on A2E-loaded retinal pigment epithelium cells. We defined 415-455 nm blue-violet light, within the solar spectrum reaching the retina, to be the spectral band that generates the highest amount of reactive oxygen species and produces the highest level of mitochondrial dysfunction, explaining its toxic effect. This study further highlights the need to filter these wavelengths from the eyes of AMD patients.