Lu Xiang

Background: Retinopathy of prematurity (ROP) is a predominant contributor to preventable childhood blindness driven by oxidative stress and inflammation, but with limited treatment options. Safe, non-invasive adjunctive strategies become attractive. Lutein displays antioxidant and anti-inflammatory properties, but its clinical efficacy remains controversial. We proposed that formulating lutein in extra-virgin olive oil (EVOO) might enhance its absorption and efficacy in ROP. Here, we evaluated the effects of lutein-in-EVOO (LEVOO) in oxygen-induced retinopathy (OIR), a mouse model of ROP. Methods: C57BL/6J mouse neonates received daily gavage of LEVOO (0.4 μg/g, 1.8 μg/g and 3.6 μg/g of lutein in EVOO) after OIR challenge from postnatal day (P) 12 to P16. Assessments were conducted at P17, including retinal vasculature, function, cytoarchitecture, inflammation, and oxidative damage; serum biochemical and antioxidant profiles; and proteomic analysis and targeted retinal metabolomic analysis. Results: Oral supplementation of LEVOO was well-tolerated and safe in mouse neonates. It reduced retinal avascular and neovascular areas, increased electroretinographic b-wave amplitudes, and restored amacrine cells and rod bipolar cells. LEVOO administration reduced oxidative damage and activated microglia. LEVOO administration inhibited the hypoxia-inducible factor-1α (HIF-1α)/macrophage migration inhibitory factor (MIF) signaling and low-density lipoprotein receptor-related protein-1 (LRP1)-dependent cyclophilin A (CypA)/matrix metalloproteinase-9 (MMP9) signaling. It also helped to partially restore retinal docosahexaenoic acid and dopamine in OIR mice. Conclusions: LEVOO demonstrated multifaceted efficacy in OIR. It reconstructed retinal vasculature, restored retinal function, and rescued neuronal cell loss with strong antioxidative and anti-inflammatory effects. Collectively, these findings establish LEVOO as a promising non-invasive complementary strategy for ROP.

Retinal ischemia (RI) is a prominent pathological feature of several ocular diseases, including diabetic retinopathy, glaucoma, and retinopathy of prematurity. These diseases are major causes of adult and childhood blindness worldwide. Retinal and optic nerve degeneration also involves non-ischemic mechanisms. Severe or sustained RI can cause irreversible retinal injury and visual impairment. RI can trigger oxidative stress, inflammatory responses, and mitochondrial dysfunction, which can contribute to cell death. Ferroptosis is a distinct form of regulated cell death characterized by the iron-dependent accumulation of lethal lipid peroxides in membrane phospholipids. Accumulating preclinical evidence indicates that ferroptosis-associated processes may contribute to retinal and optic nerve injury. Targeting ferroptosis-related pathways may offer promising approaches to mitigate cellular damage in these diseases. In this review, we summarize the ferroptosis mechanisms relevant to retinal and optic nerve injury and evaluate evidence from experimental models, cell types, pharmacological rescue studies, and genetic approaches. By comparing experimental models, cell types, and mechanistic evidence, we distinguish direct neuronal findings from non-neuronal ocular responses and assess whether the results support ferroptosis or broader oxidative stress. We also identify the evidence needed to assess the translational relevance of ferroptosis-targeted strategies in retinal and optic nerve diseases.