Oxidative Stress and Antioxidants in Age-Related Macular Degeneration

Abstract

Oxidative stress plays a crucial role in aging-related eye diseases, including age-related macular degeneration (AMD), cataracts, and glaucoma. With age, antioxidant reparative capacity decreases, and excess levels of reactive oxygen species produce oxidative damage in many ocular cell types underling age-related pathologies. In AMD, loss of central vision in the elderly is caused primarily by retinal pigment epithelium (RPE) dysfunction and degeneration and/or choroidal neovascularization that trigger malfunction and loss of photo-sensing photoreceptor cells. Along with various genetic and environmental factors that contribute to AMD, aging and age-related oxidative damage have critical involvement in AMD pathogenesis. To this end, dietary intake of antioxidants is a proven way to scavenge free radicals and to prevent or slow AMD progression. This review focuses on AMD and highlights the pathogenic role of oxidative stress in AMD from both clinical and experimental studies. The beneficial roles of antioxidants and dietary micronutrients in AMD are also summarized.

Mitochondrial damage and clearance in retinal pigment epithelial cells

“…Researchers have developed various animal and cellbased models to investigate AMD pathways, enhancing our understanding of its pathophysiology (Pennesi et al, 2012;Rho et al, 2022). However, the evidence consistently points to ageing and related oxidative stress as major contributing factors (Abokyi et al, 2020;Kushwah et al, 2023;Maurya et al, 2023;Ruan et al, 2021). Therefore, maintaining and improving physical and mental health through practices promoting 'Healthy Ageing' could potentially serve as a strategy for preventing AMD (Figure 35).…”

Cellular ROS and Antioxidants: Physiological and Pathological Role

“…Antioxidants such as lutein, zeaxanthin [37], and vitamin C [38] have been shown to confer significant benefits to ocular health, contributing to maintaining healthy eyes. These antioxidants play crucial roles in preventing oxidative stress within ocular tissues, thereby helping to preserve visual function and protect against age-related degenerative changes and cataracts [39]. Incorporating these antioxidants into therapeutic regimens supports ocular health and underscores their potential as preventive measures against eye-related conditions.…”

The protective effects of beta-mangostin against sodium iodate-induced retinal ROS-mediated apoptosis through MEK/ERK and p53 signaling pathways

“…Several mechanisms involving antioxidants, such as free-radical scavenging, can prevent the degenerative processes responsible for the aforementioned diseases. 6,7 NaIO 3 is frequently employed to explore the development of dry AMD as it induces retinal degeneration in a dose-and time-dependent fashion. NaIO 3 is a potent oxidizing agent that has found extensive use in preclinical experimental models of RPE dysfunction via ROS-mediated apoptosis in vivo and in vitro.…”

“…3,8,9 Oxidative toxicity and cell death induced by NaIO 3 have been carefully studied in several studies. [3][4][5][6][7] Therefore, there are currently a large number of studies showing that the consumption of natural foods, especially fruits and vegetables, can reduce the incidence of such degen-erative diseases. [3][4][5][6][7] Because they contain various antioxidants, such foods are considered to be highly and positively bioactive.…”

“…[3][4][5][6][7] Therefore, there are currently a large number of studies showing that the consumption of natural foods, especially fruits and vegetables, can reduce the incidence of such degen-erative diseases. [3][4][5][6][7] Because they contain various antioxidants, such foods are considered to be highly and positively bioactive. Carotenoids, polyphenols, and vitamins C and E are considered responsible for most of the food's antioxidant activity.…”