From Food to Function: Nutraceutical-Based Modulation of Mitochondrial, Inflammatory, and Epigenetic Networks in Retinal Neurodegeneration.
Retinal neurodegenerative diseases, such as age-related macular degeneration, diabetic retinopathy, glaucoma, and inherited retinal dystrophies, are major causes of irreversible vision loss worldwide. Although they originate from different causes, these disorders increasingly appear to share a network of cellular stress pathways, including impaired mitochondrial function, oxidative stress, endoplasmic reticulum proteostasis collapse, chronic neuroinflammation, epigenetic dysregulation, and activation of regulated cell death pathways. The interactions among these processes create an integrated stress network that gradually disrupts retinal homeostasis and promotes neuronal degeneration, which explains the failure of therapies targeting single molecular pathways. Nutraceutical compounds found in food are gaining interest as potential agents to support retinal health because many exhibit pleiotropic biological activities that influence mitochondrial function, inflammatory signaling, antioxidant defenses, and transcriptional regulation. Herein, we consolidate knowledge of the molecular mechanisms underlying retinal neurodegeneration and how major classes of nutraceuticals (polyphenols, carotenoids, omega-3 fatty acids, and metabolic modulators) may interact with these pathways. We also discuss key translational challenges in developing therapies, including poor bioavailability and differences between human phenotypes and model systems. Additionally, we highlight emerging concepts such as microbiome-dependent metabolism of nutraceuticals, personalized nutrition strategies, and advanced ocular drug-delivery technologies. Collectively, these findings support a systems-level framework in which selected nutraceuticals may influence multiple nodes of retinal stress biology, although clinical validation remains limited.