Microbiota-gut-brain axis: Modulation of gut microbiota in the management of Alzheimer’s disease

Abstract

Insights into the role of the gut microbiota are advancing our understanding of Alzheimer’s disease (AD), which is the most common cause of dementia and a condition characterized by progressive cognitive decline and pathological hallmarks such as amyloid beta (Aβ) plaques and neurofibrillary tangles. The gut microbiota, composed of diverse microorganisms, influences brain health through the microbiota-gut-brain axis. This review outlines how alterations in gut microbial composition and metabolites occur across different stages of cognitive decline. The microbiota-gut-brain axis mediates interactions between the gut and brain, influencing neuroinflammation, Aβ accumulation, tau pathology, and oxidative stress. Therapeutic strategies targeting gut microbiota, including diet modulation, probiotics, prebiotics, synbiotics, microbial metabolites, and fecal microbiota transplantation, have shown potential in improving cognitive function in clinical and animal studies. Despite these advances, challenges remain in addressing individual variability, standardization, and long-term safety. Personalized microbiota-based interventions may provide promising tools for the diagnosis, prevention, and treatment of AD.

Keywords

Alzheimer’s disease / Gut microbiota / Microbiota-gut-brain axis / Therapeutic strategies

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