Fig. 6.

N-Retinylidene-N-retinylethanolamine (A2E) photosensitization-mediated senescence in the pathogenesis of age-related macular degeneration (AMD). A retinal pigment epithelium (RPE) damaging factor may impair the ability of RPE cells to phagocytose photoreceptor outer segments (POS) resulting in lipofuscin accumulation (light green spots) and AMD-like phenotype. Lipofuscin contains A2E that, upon photosensitization, may induce oxidative stress, DNA damage and telomere dysfunction/loss that leads to senescence and nuclear factor kappa B subunit 1 (NF-κB)-mediated senescence-associated secretory phenotype (SASP) that may result in damaging neighboring normal RPE cells and expansion of the AMD phenotype. Activated A2E may be neutralized by antioxidants