The gut-retina axis in age-related macular degeneration: immune crosstalk and metabolite production

Area of Science:

• Ophthalmology and Microbiology
• Investigates the gut-retina axis in age-related macular degeneration (AMD) pathogenesis.

Background:

• Current therapies for dry and wet age-related macular degeneration (AMD) fail to halt or reverse disease progression.
• Emerging research highlights the gastrointestinal microbiome's role in AMD through the gut-retina axis.
• Microbial imbalance (dysbiosis) can worsen inflammation and neovascularization in AMD.

Purpose of the Study:

• To review current mechanistic insights into microbial-immune crosstalk in AMD.
• To emphasize the interplay of dysbiosis, immune activation, and metabolite signaling in AMD.
• To explore the gut-retina axis as a potential therapeutic target for AMD.

Main Methods:

• Literature review synthesizing current research on the gut microbiome and AMD.
• Analysis of mechanisms involving microbial dysbiosis, immune responses (microglial priming, inflammasome activation), and cytokine secretion (IL-6, IL-1β, TNF-α, VEGF).
• Examination of the role of microbiome-derived metabolites (short-chain fatty acids, bile acids) in AMD.

Main Results:

• Dysbiosis exacerbates AMD by promoting systemic and retinal inflammation.
• Depletion of beneficial metabolites and enrichment of specific microbes are linked to advanced AMD.
• Dietary interventions (Mediterranean, high-fiber) and experimental strategies (FMT) show promise.

Conclusions:

• The gut-retina axis, influenced by microbial-immune crosstalk and metabolite signaling, presents a promising therapeutic target for AMD.
• Dietary modifications and microbiome-targeted interventions may help manage AMD progression.
• Further research into these mechanisms could lead to novel AMD treatments.