Antibiotics are widely used to treat bacterial infections, and while generally effective, they may also negatively impact health. Antibiotic use not only affects pathogenic, but also commensal bacteria, resulting in disturbances in gut microbial composition. These perturbations can have detrimental effects on host metabolic health. To limit detrimental outcomes of antibiotic use it is important to improve microbial resilience, the ability of the microbiome to return to its initial state.

Here, we aim to investigate the potential of the prebiotic 2’-Fucosyllactose (2’-FL) to restore gut microbiota composition and activity, as well as parameters of metabolic health, after vancomycin use. In this double-blind placebo-controlled randomized intervention study, 40 adults with overweight or obesity (Body Mass Index: 25-40 kg/m²) and without impaired fasting glucose and impaired glucose tolerance received vancomycin for seven days in order to disrupt gut microbial composition. Next, participants were randomized to either 2’-FL supplementation (3*4g/day) or maltodextrin placebo (3*2g/day) for eight weeks. At baseline, after antibiotic use and after supplementation, microbial composition was assessed using metagenomic sequencing (Nanopore). Whole-body and tissue-specific insulin sensitivity were assessed from plasma glucose, insulin and free fatty acid levels measured during a 7-point Oral Glucose Tolerance Test. We hypothesized that 2’-FL supplementation would improve gut microbiome resilience after antibiotic use, thereby limiting detrimental effects on metabolic health. 

Preliminary analyses show the ability of one-week vancomycin use to disrupt gut microbial composition and diversity. Interestingly, hepatic insulin sensitivity improved after vancomycin use. Analyses assessing the potential of 2’-FL to improve microbial resilience still need to be performed.