A Comprehensive Review on the Microbial Signatures and Metabolic Mechanisms Underlying the Gut-Alzheimer's Disease Axis.

Authors

S N Amruthavarshini, Nitu Kumari, Santosh Anand

Published in

Molecular neurobiology. Volume 63. Issue 1. Jun 19, 2026. Epub Jun 19, 2026.

Abstract

Alzheimer's disease (AD) is the most common form of dementia, driven by complex interactions among aging-related biological changes, neuronal degeneration, mitochondrial dysfunction, and environmental factors. Despite extensive research, effective disease-modifying therapies remain unavailable. Increasing evidence highlights the gut-brain axis as an important contributor to AD pathogenesis, particularly through amyloid-producing gut microbes that promote immune activation, neuroinflammation, and cerebral amyloid accumulation. This review summarizes current evidence linking gut microbiota (GM) dysbiosis to AD, focusing on microbial metabolites, neuroinflammatory pathways, and microbiota-targeted therapeutic strategies. A systematic analysis of experimental and clinical studies reveals that altered gut microbial composition is associated with systemic and neuroinflammation, blood-brain barrier dysfunction, oxidative stress, and neuronal damage. Key microbial metabolites, including short-chain fatty acids and indole derivatives, exhibit neuroprotective effects by regulating immune responses, maintaining barrier integrity, and supporting neuronal energy metabolism; disruption of these metabolites may accelerate neurodegeneration. Microbiota-based interventions such as probiotics, prebiotics, dietary modification, and fecal microbiota transplantation show beneficial effects in preclinical models by restoring microbial balance and reducing neuropathological features, although clinical evidence in humans remains limited. Overall, current findings support a contributory role of gut dysbiosis in AD and suggest that targeting the GM may offer a promising complementary strategy for disease modification and future therapeutic development.

PMID:
42319691
Bibliographic data and abstract were imported from PubMed on 19 Jun 2026.

Read full publication at:
Please sign in to see all details.

Stats

1-terrible, 9-excellent. How would you rate this publication? Sign in in to submit your rating.

Post a comment

You need to be signed in to post comments. You can sign in here.

Comments

There are no comments yet.