Undaria pinnatifida fucoidan extract inhibits activation of the NF-κB signaling pathway by herpes simplex virus type 1 and prevents amyloid-β peptide synthesis in retinal pigment epithelium cells.

Neurodegenerative pathologies such as age-related macular degeneration currently have no cure or effective treatment. In this type of disease, the presence of amyloid-β peptides, oxidative stress, and inflammation trigger dysregulation of retinal pigment epithelial cells and progression toward the death of these cells, resulting in a loss of vision. The production of amyloid-β peptides, oxidative stress, and inflammation can be triggered in response to viral infections. Fucoidans are sulfated polysaccharides that are present in the cell walls of brown algae. There is a large body of literature reporting a wide range of biological properties of these compounds. In this study, we investigated whether Undaria pinnatifida fucoidan extract can prevent infection with herpes simplex virus type 1 and if the extract has antioxidant activity. We also evaluated whether, under viral infection conditions, the synthesis of amyloid-β peptide and NF-κB activation could be inhibited by the extract. The results showed for the first time that this extract can prevent viral infection in retinal pigment epithelial cells and that they can prevent the formation of amyloid-β peptide and the activation of the NF-κB pathway during viral infection. We also found that Undaria pinnatifida fucoidan extract has antioxidant activity and reduces the levels of reactive oxygen species. These data suggest that Undaria pinnatifida fucoidan extract might be effective for treating diseases triggered by viral infections, such as degenerative retinal diseases.