Research Progress on Intervention Strategies Targeting the Gut-Brain Axis in Alzheimer`s Disease.

As the most common neurodegenerative disease in the world, Alzheimer's Disease (AD) is characterized by a complex pathogenesis and a lack of effective treatments. In recent years, breakthroughs in the Gut-Brain Axis (GBA) theory have provided a new direction for AD intervention. Studies have shown that AD patients commonly exhibit gut dysbiosis, accompanied by decreased Short-Chain Fatty Acid (SCFA) levels, endotoxin leakage, and increased systemic inflammation, which accelerate cognitive decline via neuroinflammation, Aβ deposition, and synaptic dysfunction. Based on this, intervention strategies targeting the GBA have emerged as a focus of research for slowing down the pathological process of AD. In this study, we systematically summarize the mechanisms linking gut microbiota dysbiosis to AD pathology. This includes the roles of metabolites (e.g., SCFA, LPS, and TMAO) in modulating neuroinflammation and Blood-Brain Barrier (BBB) permeability, as well as the critical involvement of vagal nerve pathways in gut-brain signaling. We further explored the potential of probiotics to improve cognitive function by restoring microbial homeostasis, enhancing anti-inflammatory effects, and elevating neurotrophic factor levels; dietary interventions (e.g., the Mediterranean and MIND diets) to reduce AD risk by modulating microbial composition and metabolic activity; and Fecal Microbiota Transplantation (FMT) to reduce Aβ plaque deposition and mitigate neuroinflammation. Despite promising findings, challenges persist, including discrepancies between animal models and human subjects, individual variability in microbiota composition, and an incomplete understanding of underlying mechanisms. In the future, it will be necessary to combine multiple technologies to develop personalized intervention protocols and optimize clinical translation processes, providing a theoretical basis for the precise treatment of AD.