A study published in Genome Biology explores the dynamic effects of hypoxia on gut microbiota, focusing specifically on a strain of Blautia wexlerae, and its role in maintaining intestinal health and metabolic functions under low-oxygen conditions. The research presents a comprehensive metagenomic analysis on how exposure to hypoxia alters the gut microbial environment, providing insight into the potential therapeutic application of B. wexlerae for people exposed to high-altitude environments.
To conduct this study, bacterial DNA was extracted from fecal samples using the QIAamp DNA Stool Mini Kit, ensuring high DNA purity, which was verified by both the Nanodrop® spectrophotometer and agarose gel electrophoresis. The study employed two metagenomic assembly strategies: individual assembly (each sample assembled separately) and co-assembly (merging data based on timepoints). These two strategies allowed the construction of metagenome-assembled genomes (MAGs), which were binned using Metabat2 and Maxbin2 within MetaWRAP. This approach allowed the identification of both individual-specific and shared microbial genomes across timepoints, leading to a better understanding of microbial dynamics.
The study further validated its findings using six independent cohorts of Han Chinese residing in high-altitude regions of Tibet. These validation cohorts included individuals who had lived at high altitudes for varying durations (ranging from 6 months to more than 60 months). The microbial dynamics and gene profiles observed in these populations were consistent with the findings from the time-series cohort, further strengthening the association between hypoxia and microbial changes.
In the mice experiments, the researchers divided 24 mice into three groups: one group receiving B. wexlerae and the others serving as control groups. Fecal samples were collected at multiple time points, and whole-genome sequencing was performed to track microbial changes. The results showed that B. wexlerae significantly altered the gut microbiota composition and contributed to improved gut health under hypoxic conditions. Various health parameters such as body weight, lung function, and blood oxygen levels were measured, showing that B. wexlerae helped mitigate the adverse effects of hypoxia.
This study highlights the potential role of B. wexlerae in protecting the gut microbiota under hypoxia, especially in populations living at high altitudes. The findings suggest that specific strains of gut bacteria can play a critical role in maintaining gut health under stress, offering new avenues for therapeutic interventions for individuals exposed to high-altitude or low-oxygen environments. By using metagenomic approaches and validation cohorts, the study provides a comprehensive view of how hypoxia affects the gut microbiota and the potential benefits of targeted microbial interventions.
Sources: Genome Biology