Short-Term High-Altitude Exposure Alters Pharyngeal and Gut Microbiome

Area of Science:

• Microbiology
• Human Physiology
• Altitude Medicine

Background:

• High-altitude exposure presents physiological challenges.
• Microbial communities are increasingly recognized for their role in host adaptation.
• Understanding microbiome dynamics is crucial for high-altitude acclimatization.

Purpose of the Study:

• To investigate dynamic changes in pharyngeal and gut microbiota during high-altitude acclimatization.
• To identify specific microbial taxa associated with altitude-related physiological responses.
• To elucidate the role of the microbiome in host resilience to hypoxic environments.

Main Methods:

• Longitudinal study design with four health visits (baseline, arrival, 1-week acclimatization, return).
• Sample collection: throat swabs and fecal samples.
• Analysis: 16S rRNA amplicon sequencing, linear mixed-effects models, and LEfSe (Linear Discriminant Analysis Effect Size).

Main Results:

• Pharyngeal microbial diversity significantly altered after 1 week at high altitude (decreased Shannon index, increased Simpson index).
• Gut microbial diversity initially decreased but tended to recover after 1 week.
• Significant differences in pharyngeal microbiota composition were observed across visits; gut microbiota showed less pronounced changes.
• 11 pharyngeal and 4 gut microbes were identified as differentially abundant.

Conclusions:

• High-altitude exposure significantly disrupts pharyngeal and gut microbial diversity.
• Microbiome shifts, including changes in opportunistic pathogens, may mediate host adaptation to hypoxia.
• The study underscores the critical role of the microbiome in physiological acclimatization to high altitudes.