Antioxidant and Neuroprotective Effects of 20% Marigold Extract Oil (Lutein/Zeaxanthin Complex) in LED-induced Retinal Injury and A2E-mediated ARPE-19 Models

<h3>Background/Aim:</h3> Lutein and zeaxanthin (L/Z) are major components of macular pigment with established antioxidant and blue-light filtering properties. This study investigated the protective efficacy of a 20% marigold extract oil (L/Z complex) using both an A2E-mediated ARPE-19 cell <i>in vitro</i> phototoxicity model and a light-emitting diode (LED)-induced retinal injury rat model. <h3>Materials and Methods:</h3> <i>In vitro</i>, ARPE-19 cells were loaded with A2E and exposed to blue light (6,000 lux, 20 min). <i>In vivo</i>, rats were exposed to 750 lux LED for 48 h following 4-week oral administration of L/Z complex. Cell viability, inflammatory cytokines, antioxidant enzymes, retinal histopathology, and expression of nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase 1 (HO-1) and nuclear factor-κB (NF-κB) were evaluated. <h3>Results:</h3> In ARPE-19 cells, A2E-mediated blue light exposure reduced viability to 28.15±3.67% and markedly increased inflammatory cytokines. L/Z complex significantly reduced NF-κB, interleukin-1 beta (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) expression while enhancing HO-1 and antioxidant enzyme levels. In the rat model, L/Z complex preserved outer nuclear layer (ONL) thickness, reduced pro-inflammatory cytokines, enhanced total antioxidant capacity (TAC) and glutathione peroxidase (GSH-Px) activities, and attenuated NF-κB expression. <h3>Conclusion:</h3> The L/Z complex confers retinal protection through coordinated antioxidant and anti-inflammatory mechanisms in both cellular and animal models of retinal injury, supporting its translational potential as a nutritional intervention for retinal degeneration.