Dataset Information

Associations between gut microbiota and Alzheimer's disease, major depressive disorder, and schizophrenia.

ABSTRACT:

Background

Growing evidence has shown that alterations in the gut microbiota composition were associated with a variety of neuropsychiatric conditions. However, whether such associations reflect causality remains unknown. We aimed to reveal the causal relationships among gut microbiota, metabolites, and neuropsychiatric disorders including Alzheimer's disease (AD), major depressive disorder (MDD), and schizophrenia (SCZ).

Methods

A two-sample bi-directional Mendelian randomization analysis was performed by using genetic variants from genome-wide association studies as instrumental variables for gut microbiota, metabolites, AD, MDD, and SCZ, respectively.

Results

We found suggestive associations of host-genetic-driven increase in Blautia (OR, 0.88; 95%CI, 0.79-0.99; P = 0.028) and elevated γ-aminobutyric acid (GABA) (0.96; 0.92-1.00; P = 0.034), a downstream product of Blautia-dependent arginine metabolism, with a lower risk of AD. Genetically increased Enterobacteriaceae family and Enterobacteriales order were potentially associated with a higher risk of SCZ (1.09; 1.00-1.18; P = 0.048), while Gammaproteobacteria class (0.90; 0.83-0.98; P = 0.011) was related to a lower risk for SCZ. Gut production of serotonin was potentially associated with an increased risk of SCZ (1.07; 1.00-1.15; P = 0.047). Furthermore, genetically increased Bacilli class was related to a higher risk of MDD (1.07; 1.02-1.12; P = 0.010). In the other direction, neuropsychiatric disorders altered gut microbiota composition.

Conclusions

These data for the first time provide evidence of potential causal links between gut microbiome and AD, MDD, and SCZ. GABA and serotonin may play an important role in gut microbiota-host crosstalk in AD and SCZ, respectively. Further investigations in understanding the underlying mechanisms of associations between gut microbiota and AD, MDD, and SCZ are required.

SUBMITTER: Zhuang Z

PROVIDER: S-EPMC7532639 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Publications

Associations between gut microbiota and Alzheimer's disease, major depressive disorder, and schizophrenia.

Zhuang Zhenhuang Z Yang Ruotong R Wang Wenxiu W Qi Lu L Huang Tao T

Journal of neuroinflammation 20201002 1

<h4>Background</h4>Growing evidence has shown that alterations in the gut microbiota composition were associated with a variety of neuropsychiatric conditions. However, whether such associations reflect causality remains unknown. We aimed to reveal the causal relationships among gut microbiota, metabolites, and neuropsychiatric disorders including Alzheimer's disease (AD), major depressive disorder (MDD), and schizophrenia (SCZ).<h4>Methods</h4>A two-sample bi-directional Mendelian randomization ...[more]

PMID: 33008395

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Dataset Information

Associations between gut microbiota and Alzheimer's disease, major depressive disorder, and schizophrenia.

Background

Methods

Results

Conclusions

Publications

Associations between gut microbiota and Alzheimer's disease, major depressive disorder, and schizophrenia.

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