Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2024 Oct 19;25(20):11272.
doi: 10.3390/ijms252011272.

Novelties on Neuroinflammation in Alzheimer's Disease-Focus on Gut and Oral Microbiota Involvement

Cristina Popescu  1   2 , Constantin Munteanu  2   3 , Aurelian Anghelescu  1   2 , Vlad Ciobanu  4 , Aura Spînu  1   2 , Ioana Andone  1   2 , Mihaela Mandu  1   2 , Roxana Bistriceanu  1   2 , Mihai Băilă  1   2 , Ruxandra-Luciana Postoiu  1   2 , Andreea-Iulia Vlădulescu-Trandafir  1   2 , Sebastian Giuvara  1   2 , Alin-Daniel Malaelea  1   2 , Gelu Onose  1   2
Affiliations
Review

Novelties on Neuroinflammation in Alzheimer's Disease-Focus on Gut and Oral Microbiota Involvement

Cristina Popescu et al. Int J Mol Sci. .

Abstract

Recent studies underscore the role of gut and oral microbiota in influencing neuroinflammation through the microbiota-gut-brain axis, including in Alzheimer's disease (AD). This review aims to provide a comprehensive synthesis of recent findings on the involvement of gut and oral microbiota in the neuroinflammatory processes associated with AD, emphasizing novel insights and therapeutic implications. This review reveals that dysbiosis in AD patients' gut and oral microbiota is linked to heightened peripheral and central inflammatory responses. Specific bacterial taxa, such as Bacteroides and Firmicutes in the gut, as well as Porphyromonas gingivalis in the oral cavity, are notably altered in AD, leading to significant changes in microglial activation and cytokine production. Gut microbiota alterations are associated with increased intestinal permeability, facilitating the translocation of endotoxins like lipopolysaccharides (LPS) into the bloodstream and exacerbating neuroinflammation by activating the brain's toll-like receptor 4 (TLR4) pathways. Furthermore, microbiota-derived metabolites, including short-chain fatty acids (SCFAs) and amyloid peptides, can cross the blood-brain barrier and modulate neuroinflammatory responses. While microbial amyloids may contribute to amyloid-beta aggregation in the brain, certain SCFAs like butyrate exhibit anti-inflammatory properties, suggesting a potential therapeutic avenue to mitigate neuroinflammation. This review not only highlights the critical role of microbiota in AD pathology but also offers a ray of hope by suggesting that modulating gut and oral microbiota could represent a novel therapeutic strategy for reducing neuroinflammation and slowing disease progression.

Keywords: Alzheimer’s disease (AD); amyloid peptides; dysbiosis; gut microbiota; neuroinflammation.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflicts of interest.

Figures

Figure 1
Figure 1
The intricate relationship between neuroinflammation, microbiota, and Alzheimer’s disease.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Munteanu C., Iordan D.A., Hoteteu M., Popescu C., Postoiu R., Onu I., Onose G. Mechanistic Intimate Insights into the Role of Hydrogen Sulfide in Alzheimer’s Disease: A Recent Systematic Review. Int. J. Mol. Sci. 2023;24:15481. doi: 10.3390/ijms242015481. - DOI - PMC - PubMed
    1. Breijyeh Z., Karaman R. Comprehensive Review on Alzheimer’s Disease: Causes and Treatment. Molecules. 2020;25:5789. doi: 10.3390/molecules25245789. - DOI - PMC - PubMed
    1. 2024 Alzheimer’s disease facts and figures. Alzheimer’s Dement. 2024;20:3708–3821. doi: 10.1002/alz.13809. - DOI - PMC - PubMed
    1. Shin J.-H. Dementia Epidemiology Fact Sheet 2022. Ann. Rehabilitation Med. 2022;46:53–59. doi: 10.5535/arm.22027. - DOI - PMC - PubMed
    1. Ong S.C., Tay L.J., Ng T., Parumasivam T. Economic Burden of Alzheimer’s Disease: A Systematic Review. Value Health Reg. Issues. 2024;40:1–12. doi: 10.1016/j.vhri.2023.09.008. - DOI - PubMed

MeSH terms

LinkOut - more resources