Bridging the gap: associations between gut microbiota and psychiatric disorders

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Abstract

Background

Gut microbiota plays a pivotal role in the gut-brain axis and can influence neurodevelopment and mental health outcomes. This review summarizes the current evidence on the associations between gut microbiota alterations and various psychiatric illnesses.

Main body

The composition of the gut microbiome evolves from birth through old age, and disruptions during critical periods may increase disease risk. Factors like diet, medications, stress, and infections can disturb the gut microenvironment and lead to dysbiosis. Dysbiosis has been linked to conditions like depression, anxiety, autism, ADHD, and schizophrenia. Proposed mechanisms involve microbial regulation of neurotransmitters, inflammation, oxidative stress, blood-brain barrier permeability, and the immune system. Therapeutic strategies like probiotics, prebiotics, and faecal transplantation may modulate the gut-brain axis and microbial ecosystem. However, more research is needed to elucidate the causal microbiota-psychiatry relationship. Understanding gut-brain interactions may uncover new possibilities for preventing and managing psychiatric disorders.

Conclusion

A growing body of research points to a close relationship between gut microbiota and mental health. While the field is still emerging, dysbiosis of gut microbial ecosystem has been associated with various neuropsychiatric conditions. The underlying mechanisms likely involve the microbiota-gut-brain axis signalling pathways. Additional research with larger samples is required to establish causal links between specific microbial changes and psychiatric outcomes.

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Most cited references 181

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Diet rapidly and reproducibly alters the human gut microbiome

Lawrence A David, Corinne F. Maurice, Rachel Carmody … (2013)

Long-term diet influences the structure and activity of the trillions of microorganisms residing in the human gut 1–5 , but it remains unclear how rapidly and reproducibly the human gut microbiome responds to short-term macronutrient change. Here, we show that the short-term consumption of diets composed entirely of animal or plant products alters microbial community structure and overwhelms inter-individual differences in microbial gene expression. The animal-based diet increased the abundance of bile-tolerant microorganisms (Alistipes, Bilophila, and Bacteroides) and decreased the levels of Firmicutes that metabolize dietary plant polysaccharides (Roseburia, Eubacterium rectale, and Ruminococcus bromii). Microbial activity mirrored differences between herbivorous and carnivorous mammals 2 , reflecting trade-offs between carbohydrate and protein fermentation. Foodborne microbes from both diets transiently colonized the gut, including bacteria, fungi, and even viruses. Finally, increases in the abundance and activity of Bilophila wadsworthia on the animal-based diet support a link between dietary fat, bile acids, and the outgrowth of microorganisms capable of triggering inflammatory bowel disease 6 . In concert, these results demonstrate that the gut microbiome can rapidly respond to altered diet, potentially facilitating the diversity of human dietary lifestyles.

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Microbial ecology: human gut microbes associated with obesity.

Ruth E Ley, Peter J. Turnbaugh, Samuel Klein … (2006)

Two groups of beneficial bacteria are dominant in the human gut, the Bacteroidetes and the Firmicutes. Here we show that the relative proportion of Bacteroidetes is decreased in obese people by comparison with lean people, and that this proportion increases with weight loss on two types of low-calorie diet. Our findings indicate that obesity has a microbial component, which might have potential therapeutic implications.

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Host microbiota constantly control maturation and function of microglia in the CNS.

Daniel Erny, Anna de Angelis, Diego Jaitin … (2015)

As the tissue macrophages of the CNS, microglia are critically involved in diseases of the CNS. However, it remains unknown what controls their maturation and activation under homeostatic conditions. We observed substantial contributions of the host microbiota to microglia homeostasis, as germ-free (GF) mice displayed global defects in microglia with altered cell proportions and an immature phenotype, leading to impaired innate immune responses. Temporal eradication of host microbiota severely changed microglia properties. Limited microbiota complexity also resulted in defective microglia. In contrast, recolonization with a complex microbiota partially restored microglia features. We determined that short-chain fatty acids (SCFA), microbiota-derived bacterial fermentation products, regulated microglia homeostasis. Accordingly, mice deficient for the SCFA receptor FFAR2 mirrored microglia defects found under GF conditions. These findings suggest that host bacteria vitally regulate microglia maturation and function, whereas microglia impairment can be rectified to some extent by complex microbiota.