Stress Reaction in Outer Segments of Photoreceptors after Blue Light Irradiation

• DOI: 10.1371/journal.pone.0071570
• Publication Date: 2013-09-11T21:14:55Z
• Authors: Cora Roehlecke; Ulrike Schumann; Marius Ader; Coy Brunssen; Silvia Bramke; Henning Morawietz; Richard H. W. Funk
• Keywords: Apocynin; Mitochondrial ROS

The retina is prone to oxidative stress from many factors which are also involved in the pathogenesis of degenerative diseases. In this study, we used application blue light as a physiological factor. aim study was identify major source intracellular ROS that mediates light-induced detrimental effects on cells may lead cytotoxicity. We hypothesized outer segments induced generation. photoreceptors, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (Nox) enzymes and recently found respiratory chain complexes represent for reactive oxygen species (ROS), beside mitochondria chromophores. Therefore, investigated hypothesis analysed exact localization photoreceptors an organotypic culture system mouse retinas. Whole eyeball cultures were irradiated with visible (405 nm) output power 1 mW/cm². Blue impingement increase production (detected by H2DCFDA live retinal explants), particularly strong photoreceptor segments. Nox-2 Nox-4 proteins sources photoreceptors; Nox inhibitor apocynin decreased stimulated light. Concomitantly, enzyme SOD-1, member antioxidant defense system, indicator molecules protein oxidation (CML) lipid (MDA 4-HNE) increased Interestingly, showed mitochondrial-like membrane potential demonstrated using two dyes (JC-1 TMRE) normally exclusively associated mitochondria. As mitochondria, these indicated decrease hypoxic states or cell situations. present demonstrates generation occurs directly after irradiation.