The Role of Gut Microbiota in Pathogenesis of Alzheimer's Disease.

This paper describes the effects of the gut microbiota on the pathogenesis of Alzheimer's pathology by evaluating the current original key findings and identifying gaps in the knowledge required for validation. The diversity of the gut microbiota declines in the elderly and in patients with Alzheimer's disease. Restoring the diversity with probiotic treatment alleviates the psychiatric and histopathological findings. This presents a problem: How does gut microbiota interact with the pathogenesis of Alzheimer's disease? The starting point of this comprehensive review is addressing the role of bacterial metabolites and neurotransmitters in the brain under various conditions, ranging from a healthy state to aging and disease. In the light of current literature, we describe three different linkages between the present gut microbiome hypothesis and the other major theories for the pathogenesis of Alzheimer's disease as follows: bacterial metabolites and amyloids can trigger central nervous system inflammation and cerebrovascular degeneration; impaired gut microbiome flora inhibits the autophagy-mediated protein clearance process; and gut microbiomes can change the neurotransmitter levels in the brain through the vagal afferent fibers. This article is protected by copyright. All rights reserved.

This article is protected by copyright. All rights reserved.

KEYWORDS: Alzheimer's disease; Autophagy; Gut microbiota; Gut-brain axis; Inflammation; Neurodegenerative diseases

PMID: 30920075 DOI: 10.1111/jam.14264