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Background: Previously, we showed that serum malondialdehyde (MDA) was significantly higher in patients with neovascular age-related macular degeneration (nAMD) than in those without AMD. The Diacron reactive oxygen metabolites (d-ROMs) and biological antioxidant potential (BAP) tests are known markers of oxidative stress. The aim of this study was to use d-ROMs and BAP tests to evaluate changes in systemic oxidative stress in patients with nAMD., Methods: Blood serum samples were collected from 34 patients with nAMD (mean age: 76.5 ± 7.7 years; 22 men) and 20 control subjects (mean age: 62.9 ± 14.0 years; 10 men), and d-ROMs and BAP tests were examined., Results: In men, the mean level of d-ROMs for the nAMD patients was significantly higher than that for the controls (312.0 ± 52.4 vs. 275.1 ± 45.5 U.CARR, respectively; P < .05). There was a significant correlation between d-ROM level and CNV lesion area in the male nAMD group (r = .42, P = .05). There were no significant differences in mean BAP test results between the nAMD patients and controls for either sex (men: 2241 ± 549 vs. 2136 ± 246 μmol/L; women: 2263 ± 292 vs. 2335 ± 161 μmol/L)., Conclusion: The d-ROMs test may provide a useful indicator of nAMD in men but not in women.

Purpose . It is a matter of increasing concern that exposure to light-emitting diodes (LED), particularly blue light (BL), damages retinal cells. This study aimed to investigate the retinal pigment epithelium (RPE) damage caused by BL and to elucidate the role of nuclear factor (erythroid-derived)-related factor 2 (Nrf2) in the pathogenesis of BL-induced RPE damage. Methods . ARPE-19, a human RPE cell line, and mouse primary RPE cells from wild-type and Nrf2 knockout ( Nrf2 -/- ) mice were cultured under blue LED exposure (intermediate wavelength, 450 nm). Cell death rate and reactive oxygen species (ROS) generation were measured. TUNEL staining was performed to detect apoptosis. Real-time polymerase chain reaction was performed on NRF2 mRNA, and western blotting was performed to detect Nrf2 proteins in the nucleus or cytoplasm of RPE cells. Results . BL exposure increased cell death rate and ROS generation in ARPE-19 cells in a time-dependent manner; cell death was caused by apoptosis. Moreover, BL exposure induced NRF2 mRNA upregulation and Nrf2 nuclear translocation in RPE. Cell death rate was significantly higher in RPE cells from Nrf2 . The Nrf2 pathway plays an important role in protecting RPE cells against BL-induced oxidative stress.-/- mice than from wild-type mice. Conclusions . The Nrf2 pathway plays an important role in protecting RPE cells against BL-induced oxidative stress.

Age-related macular degeneration (AMD) is a major cause of blindness in developed countries and is closely related to oxidative stress, which leads to lipid peroxidation. Malondialdehyde (MDA) is a major byproduct of polyunsaturated fatty acid (PUFA) peroxidation. Increased levels of MDA have been reported in eyes of AMD patients. However, little is known about the direct relationship between MDA and AMD. Here we show the biological importance of MDA in AMD pathogenesis. We first confirmed that MDA levels were significantly increased in eyes of AMD patients. In ARPE-19 cells, a human retinal pigment epithelial cell line, MDA treatment induced vascular endothelial growth factor (VEGF) expression alternation, cell junction disruption, and autophagy dysfunction that was also observed in eyes of AMD patients. The MDA-induced VEGF increase was inhibited by autophagy–lysosomal inhibitors. Intravitreal MDA injection in mice increased laser-induced choroidal neovascularization (laser-CNV) volumes. In a mouse model fed a high-linoleic acid diet for 3 months, we found a significant increase in MDA levels, autophagic activity, and laser-CNV volumes. Our study revealed an important role of MDA, which acts not only as a marker but also as a causative factor of AMD pathogenesis-related autophagy dysfunction. Furthermore, higher dietary intake of linoleic acid promoted CNV progression in mice with increased MDA levels. [ABSTRACT FROM AUTHOR]