Oral Microbiota Taxa and Pri-miRNA Expression in Bipolar Disorder: A Case-Control Study.

Area of Science:

• Microbiology
• Neuroscience
• Genetics

Background:

• Emerging research links gut microbiota dysbiosis to psychiatric symptoms.
• The oral microbiome's role in mood disorders, including bipolar disorder (BD), is increasingly recognized.
• Investigating oral microbial taxa and inflammation-related pri-miRNAs offers insights into the oral-gut-brain axis.

Purpose of the Study:

• To investigate oral microbial composition in bipolar disorder (BD) patients.
• To assess the expression of inflammation-related pri-miRNAs (146a and 155) in BD.
• To explore the potential of oral microbiota and pri-miRNAs as biomarkers in BD.

Main Methods:

• Matched case-control study with 25 BD patients and 46 controls.
• Salivary samples analyzed for microbial profiling using real-time qPCR.
• Pri-miRNA 146a and 155 expression assessed via RT-qPCR.

Main Results:

• Significant reductions in oral α-Proteobacteria, γ-Proteobacteria, and Actinobacteria in BD patients (p < 0.01).
• A higher Firmicutes/Bacteroidetes ratio observed in the BD cohort.
• No significant differences in pri-miRNA 146a and 155 expression between BD patients and controls.

Conclusions:

• Oral microbiota composition is altered in BD patients, potentially affecting systemic homeostasis and gut-brain axis interactions.
• Pri-miRNAs 146a and 155 did not serve as distinguishing biomarkers for BD status.
• Findings are preliminary, highlighting the need for larger, longitudinal studies on oral microbiome's role in BD pathogenesis.