What are the some of the latest research papers related to microbiome and HIV infections? In this post we will revisit some of them.
Gut Microbes and HIV Medications: A Link to Weight Gain?
A recent study has connected certain HIV medications to abnormal weight gain, possibly due to interactions with gut bacteria.
Researchers examined data from 121 participants, most of whom were already undergoing HIV therapy. The focus was on two commonly prescribed antiretroviral drugs: dolutegravir and bictegravir, both from the class of integrase strand transfer inhibitors.
Interestingly, while overall gut microbial diversity did not correlate with weight changes, specific bacterial species were strongly associated with either the drug type or the direction of weight change. Using advanced statistical models and machine learning, the team identified four distinct microbial groups that played a role.
Their model accounted for nearly 16% of the variability in weight gain, independent of age, sex, or body mass index. This puts into the focus the gut microbiome as a potentially important factor in how individuals respond to certain HIV medications.
Azithromycin: Lung Benefits, but Gut Costs for Children
Another study focused on children and adolescents with HIV-associated chronic lung disease, testing the impact of the antibiotic azithromycin. While the drug was found to significantly reduce lung flare-ups, it also caused lasting changes to the gut microbiome.
More than 300 young participants received either weekly doses of azithromycin or a placebo over a 48-week period. Those on the antibiotic showed a marked decline in gut bacterial diversity compared to the placebo group. In total, 27 types of bacteria were found in significantly different amounts between the groups.
One notable change was the long-term depletion of Campylobacter species, which remained low even six months after treatment ended. Additionally, natural interactions between bacterial species were weaker in the azithromycin group, suggesting a disruption in microbial balance.
Why Some Patients Don’t Fully Recover on ART
The third study sheds light on why some people on antiretroviral therapy (ART) don’t experience full immune recovery, even when the virus is suppressed. These individuals, known as “immunological non-responders”, continue to face higher health risks despite treatment.
Researchers examined a specific type of immune cell in the gut called regulatory T cells (Tregs), which are crucial for maintaining immune balance. Surprisingly, while non-responders had more Tregs, the cells functioned poorly. They were less effective at controlling inflammation, more prone to cell death, and displayed abnormal energy metabolism.
A key finding was that these patients also had fewer gut bacteria that produce short-chain fatty acids (SCFAs), compounds known to support Treg health and function. In laboratory experiments, when SCFAs were introduced, the dysfunctional Tregs improved significantly.
These results suggest that targeting the gut microbiome, through diet, supplements, or probiotics, might help improve immune outcomes for those who don’t fully benefit from ART.
