The potential of marine resources for retinal diseases: a systematic review of the molecular mechanisms

Abstract

We rely on vision more than on any other sense to obtain information about our environment. Hence, the loss or even impairment of vision profoundly affects our quality of life. Diet or food components have already demonstrated beneficial effects on the development of retinal diseases. Recently, there has been a growing interest in resources from marine animals and plants for the prevention of retinal diseases through nutrition. Especially fish intake and omega-3 fatty acids have already led to promising results, including associations with a reduced incidence of retinal diseases. However, the underlying molecular mechanisms are insufficiently explained. The aim of this review was to summarize the known mechanistic effects of marine resources on the pathophysiological processes in retinal diseases. We performed a systematic literature review following the PRISMA guidelines and identified 107 studies investigating marine resources in the context of retinal diseases. Of these, 46 studies described the underlying mechanisms including anti-inflammatory, antioxidant, antiangiogenic/vasoprotective, cytoprotective, metabolic, and retinal function effects, which we critically summarize. We further discuss perspectives on the use of marine resources for human nutrition to prevent retinal diseases with a particular focus on regulatory aspects, health claims, safety, and bioavailability.

Evaluation of the Effects of Fucoidans from Fucus Species and Laminaria hyperborea against Oxidative Stress and Iron-Dependent Cell Death

“…They are also antiangiogenic by counteracting vascular endothelial growth factor [4,[9][10][11][12]. Furthermore, high-molecular weight fucoidans have been demonstrated to reduce oxidative stress [13,14].…”

“…Oxidative stress is the imbalance between the generation of reactive oxygen or lipid species and the ability of the cells to clear them. Oxidative stress is a hallmark of many retinal diseases, neurodegeneration, and brain injury [13,14]. It therefore presents an important therapeutic target.…”

“…Furthermore, excessive iron is present after bleeding in the eye or in the brain, such as in subretinal, subarachnoid or intracerebral hemorrhage [18]. The cells that are mostly affected by oxidative stress in the eye are those of the retinal pigment epithelium (RPE) owing to their high lipid content, the phagocytic activity of the photoreceptor outer segment, and the abundance of mitochondria [13]. While RPE cells are crucial for oxidative stress protection in the retina, long-term exposure decreases their defense ability over time.…”

From the Sea for the Sight: Marine Derived Products for Human Vision

“…In recent years, marine resources have become increasingly interesting for the treatment and prevention of retinal diseases (Krueger et al, 2021 ). Marine environment offers a huge chemical diversity of bioactive molecules that can be used in medical, cosmetic, nutritional and other biotechnological products (Krueger et al, 2021 ), with at least half of them comprising human health potential applications. The Earth's surface is covered by over 70% of water, that hosts the greatest diversity of organisms.…”

“…A number of marine natural products (NPs) have been described to exert neuroprotective effects in the context of neurodegenerative diseases (Choi and Choi, 2015 ; Brillatz et al, 2018 ), and several studies highlighted marine resources with a strong potential in prevention or slowing of retinal diseases by exerting anti-inflammatory, antioxidant, antiangiogenic/vasoprotective, and cytoprotective activities, or ameliorating retinal function (Krueger et al, 2021 ). Marine resources, which can be processed as food, with beneficial effect on the prevention or progression of retinal diseases has already been described in several studies (Broadhead et al, 2015 ; Dow et al, 2018 ; Eggersdorfer and Wyss, 2018 ; Rinninella et al, 2018 ; Wong et al, 2018 ; Chapman et al, 2019 ) and reviewed recently (Krueger et al, 2021 ). However, although the consumption of fish is considered to be safe, some adverse health impacts remain with certain fish and shellfish containing chemicals or illness-causing microorganisms due to ocean pollution.…”