Salivary Microbiota Associated with Peripheral Microvascular Endothelial Dysfunction.

Area of Science:

• Microbiology
• Cardiovascular Science
• Gerontology

Background:

• Oral health is linked to atherosclerotic cardiovascular disease (ACVD).
• Previous studies identified salivary microbiota in ACVD patients.
• The role of salivary microbiota in early stages of endothelial dysfunction, prior to ACVD, is unknown.

Purpose of the Study:

• To investigate salivary microbiota characteristics in individuals with peripheral microvascular endothelial dysfunction.
• To determine if salivary microbiota can distinguish between normal and impaired endothelial function.

Main Methods:

• 16S rRNA metagenomic analysis of saliva from 172 elderly individuals without ACVD.
• Assessment of peripheral microvascular endothelial function using reactive hyperemia index (RHI).
• Comparison of salivary microbiota across normal (RHI ≥ 2.10), borderline, and abnormal (RHI < 1.67) endothelial function groups.
• Application of machine learning (Extra Trees classifier) for discrimination analysis.

Main Results:

• Individuals with abnormal endothelial function had a higher number of operational taxonomic units (OTUs) compared to the normal group (p=0.037).
• Significant differences in overall salivary microbiota structure were observed between normal and abnormal groups (p=0.038).
• Machine learning model achieved an AUC of 0.810 in discriminating between normal and abnormal endothelial function based on salivary microbial composition.

Conclusions:

• Salivary microbiota composition is distinct in individuals with endothelial dysfunction compared to those with normal function.
• These findings suggest a potential association between salivary microbiota and peripheral microvascular endothelial function.
• Salivary microbiota may serve as a biomarker for early detection of endothelial dysfunction.