[Light stress-induced damage to intracellular membrane organelles and its preventive strategies].

Photoreceptor cells in the retina are highly specialized sensory cells that function as light receptors. During the conversion of light into neural signals, photoreceptors are constantly exposed to oxidative stress. Although environmental stressors, such as excessive light exposure, have been implicated in the progression of various retinal diseases, including dry age-related macular degeneration (AMD), the molecular mechanisms underlying the light-induced stress response remain incompletely elucidated. Excessive light exposure triggers the endoplasmic reticulum (ER) stress response in cells and also induces mitochondrial dysfunction characterized by depolarization and fragmentation, ultimately leading to cell death. We have shown that compounds derived from natural products, such as delphinidins and pentadecyl, exert protective effects against blue light-induced cellular damage. Furthermore, crocetin, a natural carotenoid pigment, has been shown to suppress ultraviolet-A (UV-A)-induced mitochondrial fragmentation in corneal epithelial cells. In this review, we provide an overview of light stress-induced injuries to intracellular membrane organelles, particularly mitochondria and the ER, and the cellular response mechanisms that are mediated through these organelles. These findings suggest that maintaining the homeostasis of intracellular membrane organelles represents an important therapeutic target for the prevention and treatment of retinal degenerative diseases.