Therapeutic effect of probiotics on metabolic indices and clinical signs in age-related macular degeneration

Targeting the Gut–Eye Axis: An Emerging Strategy to Face Ocular Diseases

“…Based on these advantages, probiotics have been considered a potential treatment for various diseases associated with GM dysbiosis, including intestinal bowel syndrome, ulcerative colitis, rheumatoid arthritis, major depressive disorder, and even cancer [189][190][191][192]. Although in the context of eye disorders the evidence remains scarce, results from preclinical studies are promising, and preliminary data coming from human studies are encouraging the design of further clinical trials [193][194][195][196] (Table 1) [197][198][199][200][201][202][203][204][205][206][207][208][209][210][211][212][213]. There is evidence that mice with ocular inflammation receiving eye drops containing the cell-free supernatant of the probiotic Lactiplantibacillus plantarum show reduced ocular inflammation, lower amount of infiltrating inflammatory cells, and diminished levels of the pro-inflammatory cytokines TNF-α and IFN-γ [205].…”

“…Of note, these benefits are accompanied by increased levels of brain-derived neurotrophic factor (BDNF), which has a protective role against retinal damage [222]. Concerning oxidative stress, results obtained from a randomized controlled trial involving 57 patients with AMD showed that an 8-week intake of a probiotic mixture containing species from Bacillus, Lactobacillus, and Bifidobacterium lowers the levels of the pro-oxidant factor malondialdehyde (MDA) while systemically increasing the total antioxidant capacity [201]. However, the absence of a clear clinical effect associated with the antioxidant improvements may suggest that longer treatment periods are required to achieve a therapeutic benefit.…”

A narrative review on dietary components and patterns and age-related macular degeneration

“…Probiotics are one of the issues addressed to ensure intestinal microbiota modulation. In a randomised, double-blind, placebocontrolled study, participants aged between 50 and 85 years with AMD took either a probiotic capsule or a placebo daily for 8 weeks (253) . The results showed that probiotic supplementation led to increased plasma total antioxidant capacity and HDL-cholesterol levels while reducing malondialdehyde levels, indicating a decrease in oxidative stress and improved antioxidant status.…”