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The relationship between Alzheimer's disease and intestinal microflora structure and inflammatory factors
Su-Shan Wang1, Xiao-Hui Li2, Ping Liu1
1Department of General Practice, The Sixth Medical Center of PLA General Hospital, Beijing, China.
Abstract:
To analyze the structural characteristics of intestinal microflora and changes of serum inflammatory factors of the Alzheimer's disease, and to explore the relationship between them and dementia, we selected 30 patients in the AD group and 30 patients in the normal group, and collected stool samples to analyze the intestinal flora structure characteristics of the two groups of patients, and statistically analyzed the inflammatory cytokines TNF-α, IL-1β, IL-6, and IL-8 by ELISA from the venous blood of the two groups. The results show that the dominant Bacteroides in the two groups are Bacteroides, Firmicutes, Proteobacteria, and Actinobacteria. The abundance of Bacteroides, Firmicutes, and Proteobacteria in the AD group shows a statistical difference. At the genus level, the abundance of anti-inflammatory bacteria such as Lactobacillus, Bifidobacterium, and Ruminococcus drops in AD group, while the abundance of pro-inflammatory bacteria such as Escherichia and Enterococcus raises. Statistical analysis of inflammatory cytokines in the two groups suggests that TNF-α and IL-6 levels significantly increase in the AD group, with statistical differences. Therefore, it is speculated that the increased abundance of pro-inflammatory bacteria in intestinal flora may lead to or aggravate neuroinflammation through the release of inflammatory factors, thus further leading to the occurrence and development of AD.
Insights
Alzheimer's disease (AD) is linked to gut bacteria changes. Pro-inflammatory bacteria increase, while anti-inflammatory bacteria decrease, potentially driving neuroinflammation and AD progression.
Area of Science:
- Microbiology
- Neuroscience
- Immunology
Background:
- Alzheimer's disease (AD) is a progressive neurodegenerative disorder.
- The gut microbiome's role in neurological health is increasingly recognized.
- Alterations in gut microbiota composition are observed in various diseases.
Purpose of the Study:
- To investigate the structural characteristics of intestinal microflora in Alzheimer's disease (AD) patients.
- To analyze changes in serum inflammatory factors in AD patients.
- To explore the relationship between gut microbiota and dementia in AD.
Main Methods:
- Collected stool samples from 30 AD patients and 30 healthy controls.
- Analyzed intestinal flora structure using [specific method not detailed in abstract].
- Measured serum inflammatory cytokines (TNF-α, IL-1β, IL-6, IL-8) via ELISA.
Main Results:
- Dominant phyla (Bacteroides, Firmicutes, Proteobacteria, Actinobacteria) showed differences in abundance between groups.
- AD group exhibited decreased abundance of beneficial bacteria (Lactobacillus, Bifidobacterium, Ruminococcus).
- AD group showed increased abundance of pro-inflammatory bacteria (Escherichia, Enterococcus) and elevated serum TNF-α and IL-6 levels.
Conclusions:
- Gut microbiota dysbiosis, characterized by increased pro-inflammatory bacteria, is associated with Alzheimer's disease.
- This dysbiosis may contribute to neuroinflammation via inflammatory factor release, potentially driving AD pathogenesis.
- Targeting gut microbiota could offer a novel therapeutic strategy for AD.
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