The gut microbiota and depressive symptoms across ethnic groups

Abstract

The gut microbiome is thought to play a role in depressive disorders, which makes it an attractive target for interventions. Both the microbiome and depressive symptom levels vary substantially across ethnic groups. Thus, any intervention for depression targeting the microbiome requires understanding of microbiome-depression associations across ethnicities. Analysing data from the HELIUS cohort, we characterize the gut microbiota and its associations with depressive symptoms in 6 ethnic groups (Dutch, South-Asian Surinamese, African Surinamese, Ghanaian, Turkish, Moroccan; N = 3211), living in the same urban area. Diversity of the gut microbiota, both within (α-diversity) and between individuals (β-diversity), predicts depressive symptom levels, taking into account demographic, behavioural, and medical differences. These associations do not differ between ethnic groups. Further, β-diversity explains 29%–18% of the ethnic differences in depressive symptoms. Bacterial genera associated with depressive symptoms belong to mulitple families, prominently including the families Christensenellaceae, Lachnospiraceae, and Ruminococcaceae. In summary, the results show that the gut microbiota are linked to depressive symptom levels and that this association generalizes across ethnic groups. Moreover, the results suggest that ethnic differences in the gut microbiota may partly explain parallel disparities in depression.

multimedia: Multimodal Mediation Analysis of Microbiome Data

“…Studies of the gut-brain axis have yielded experimental evidence for interactions between the gut microbiome and the brain. For example, germ-free mice colonized with the microbiota from human patients with clinical depression develop depression-like symptoms [28, 11], and observational studies have linked particular bacterial taxa to depression [2, 35]. Given this growing body of evidence, a team from the UW-Madison Center for Healthy Minds and the Wisconsin Institute for Discovery profiled microbiome composition, surveyed psychological symptoms, and tracked behavior change among 54 subjects before and after participation in a two-month mindfulness training [7, 20] – see the Methods and Materials for details of the study design and data processing.…”

“…experimental evidence for interactions between the gut microbiome and the brain. For example, germ-free mice colonized with the microbiota from human patients with clinical depression develop depression-like symptoms [28,11], and observational studies have linked particular bacterial taxa to depression [2,35]. Given this growing body of evidence, For mediation and outcome models, we apply ridge and logistic-normal multinomial regressions, respectively [22,54].…”

A microfluidic-based gut-on-a-chip model containing the gut microbiota of patients with depression reveals physiological characteristics similar to depression

“…The fundamental mechanisms underlying depression persist as a vital and yet unresolved research field. Jos A. Bosch et al 8 discovered a correlation between gut microbiota and depression levels, which appeared to be consistent across various racial groups. Xi Hu et al 9 performed a comprehensive shotgun metagenomic analysis of fecal cross-sectional samples involving individuals diagnosed with depression ( n = 138) and a healthy control cohort ( n = 155).…”

Toward understanding links between the microbiome and neurotransmitters

“…The composition and activity of the gut microbiota is associated with both healthy and disordered neurological activity. In humans, alterations in the composition of the microbiota have been associated with neurodevelopmental conditions like autism spectrum disorder (ASD), 4 affective disorders like depression, 5 and neurodegenerative diseases like Parkinson's disease 6 . Most of these connections have been descriptive, revealing correlations between the taxonomic or genetic composition of the microbiota and these conditions.…”