In a recent study published in Nature Mental Health, researchers characterized brain-gut microbiome (BGM) patterns related to stress resilience.
Study: Stress-resilience impacts psychological wellbeing as evidenced by brain–gut microbiome interactions. Image Credit: SewCreamStudio/Shutterstock.com
Background
Resilience refers to beneficial outcomes in response to stressful events or threats and involves change acceptance, tenacity, negative affect tolerance, and the ability to recover following a stressful event.
Research has been mostly centered on the correlations between resilience and personality traits, social factors, and behavioral/emotional regulation strategies.
The composition and function of the human microbiome have been linked to stress-related disorders. The gut microbiome can modulate psychological functioning via the BGM system and has been implicated in conferring stress resilience.
This suggests that the microbiome may harbor metabolites with potential therapeutic effects. However, no study has elucidated an integrative biological profile of resilience.
About the study
In the present study, researchers investigated the relationship of resilience with clinical phenomes, neural characteristics, and microbiome function. This study was a secondary data analysis pooled from two studies. Participants were recruited from a community in Los Angeles.
Individuals were excluded if they had neurological conditions, abdominal surgery, psychiatric illnesses, substance use, antibiotic/probiotic use, or were pregnant or breastfeeding, among others.
All subjects underwent multimodal brain magnetic resonance imaging (MRI), provided stool samples, and completed questionnaires.
Questionnaire data included body mass index (BMI), physical activity, Connor-Davidson resilience scale (CD-RISC), socioeconomic status, state-trait anxiety inventory (STAI), perceived stress scale (PSS), hospital anxiety and depression scale (HADS), positive and negative affect schedule, diet, and patient-reported outcomes measurement information system (PROMIS) sleep scale.
Other measures included a patient health questionnaire, coping strategies questionnaire, everyday discrimination score, behavioral inhibition/approach system, five facet mindfulness (FFM), multiple ability self-report questionnaire (MASQ), pain catastrophizing scale, early trauma inventory, visceral sensitivity index, pain vigilance and awareness questionnaire, international personality pool (IPIP), and normal personality assessment. DNA was extracted from stool samples for 16S rRNA gene sequencing.
Further, fecal samples were processed and run through a global HD4 metabolomics platform. RNA extraction and meta-transcriptomic sequencing were performed.
The team leveraged the data integration analysis for biomarker discovery using the latent components (DIABLO) approach to elucidate interactions among clinical/behavioral, central (brain), and peripheral (metabolome, microbiome) markers associated with resilience phenotypes.
Findings
Overall, the cohort comprised 116 individuals, including 71 females. There were no significant differences in alpha and beta diversities between high- (HR) and low-resistance (LR) groups.
DIABLO analysis revealed a highly correlated omics signature, distinguishing those with low versus high psychological resilience. DIABLO-selected variables included 45 features (13 clinical, three metabolomes, five resting-state functional MRI, six structural MRI, two diffusion MRI, and 16 transcriptome variables).
Clinical variables included IPIP neuroticism and extraversion, HAD anxiety and depression, STAI anxiety, MASQ verbal memory, attention, visual perception, and language, PSS score, FFM total score, and non-judgment and describing sub-scores.
The HR group showed higher mean levels of mindfulness and extraversion but lower average levels of neuroticism, anxiety, difficulties with attention, verbal memory, language, visual perception, and perceived stress than the LR group.
Metabolome variables included creatine, dimethylglycine (DMG), and N-acetylglutamate (NAG). On average, NAG and DMG levels were higher in the HR group than in the LR group. Creatine levels were similar between groups.
Briefly, the average levels of bacterial transcriptomes linked to genetic propagation, anti-inflammation, metabolism, and environmental adaptation were elevated in the HR group.
The HR group had lower average levels of all structural MRI features but had higher levels of all resting-state functional MRI features.
Among diffusion MRI features, the HR group exhibited lower mean bilateral subcallosal gyrus connections but higher connections between the right hippocampus and (the right) lateral orbital gyrus. Two CD-RISC factors (persistence and control) showed a strong association with these DIABLO variables.
Conclusions
The study illustrated that several BGM markers could differentiate HR individuals from LR subjects. The HR group showed adaptive psychological features, neurological signatures supporting cognitive-emotional connections and emotion regulation, and microbiome function facilitating gut health.
Notably, the two groups were the most robustly differentiated by bacterial transcriptomes. The findings suggest that the gut microbiome and brain features build stress resilience.