Researchers analyzing fecal samples from 94 men with HIV in the Czech Republic discovered that gut microbial diversity and co-occurrence patterns shift significantly depending on antiretroviral therapy duration.
Microbial Diversity and ART Duration in HIV Cohorts
Modern antiretroviral therapy effectively suppresses viral loads, yet HIV persists as a chronic condition with lasting systemic effects on gut microbial ecology. A comprehensive analysis of fecal bacterial and fungal profiles from 94 men with HIV represented the largest cohort of its kind in the Czech Republic, giving researchers a clear window into how treatment regimens shape the human intestinal environment.
Bacterial profiles across the cohort proved heavily dominated by Bacillota and Bacteroidota. Among bacterial genera, Prevotella emerged as the most abundant, alongside various genera linked to short-chain fatty acid production, including Faecalibacterium. Meanwhile, the mycobiome exhibited marked inter-individual variability, with Saccharomyces standing out as the dominant fungal genus.
Ecological network analysis revealed that microbial interactions differ noticeably between treatment-duration groups. Participants with shorter antiretroviral therapy duration displayed a more interconnected microbial network, and bacterial alpha diversity also differed significantly based on treatment length.
Viral Loads, Triglycerides, and Specific Taxa Associations
Digging deeper into host parameters, investigators found distinct correlations between specific microbial communities and blood markers. Several Prevotella-related taxa alongside members of the Lachnospiraceae family showed clear associations with viral load.
Triglyceride levels also mapped closely to specific bacterial populations. Researchers observed that lipid measurements correlated with taxa including Alloprevotella and Prevotella 9, reinforcing the idea that microbiome composition mirrors metabolic health parameters even under viral suppression.
Ultimately, the data suggests that differences tied to treatment duration show up more clearly in microbial co-occurrence patterns rather than in overall taxonomic community composition.
How Prevotella Amplifies Mucosal Inflammation
While human cohorts map these associations, animal models help untangle whether these microbes actively drive disease or merely expand alongside inflammation. Colonizing mice with members of the Prevotella genus exacerbates intestinal inflammation and increases host susceptibility to mucosal injury.
The mechanism behind this flare-up involves metabolic shifts inside the gut ecosystem. Prevotella intestinalis alters both the composition and function of the microbiome, which leads directly to a sharp reduction in short-chain fatty acids—specifically acetate—during steady-state conditions.
This metabolic shortage triggers a cascade that lowers intestinal interleukin-18 levels. When researchers supplemented interleukin-18 back into Prevotella-colonized mice, the treatment successfully reduced intestinal inflammation, proving that metabolic pathway disruptions drive the immune response.
Dietary Context and Autoimmune Implications
The biological role of Prevotella remains complex and seemingly contradictory across different human populations. High prevalence and relative abundance of Prevotella typically characterize non-Western populations consuming plant-rich diets, where the genus can aid glucose metabolism stimulated by prebiotics.
In stark contrast, other clinical observations link overabundances of specific species, such as Prevotella copri, to autoimmune conditions, insulin resistance, and gut inflammation. An overabundance of this organism was documented in new-onset rheumatoid arthritis patients and individuals exhibiting systemic autoimmunity associated with rheumatoid arthritis before clinical symptoms ever manifested.
