Patients who receive eradication therapy for Helicobacter pylori infection exhibit changes in their gut microbiota and decreased ghrelin concentrations, according to results of a prospective case control study published in Frontiers in Medicine.
Investigators conducted a study to determine the relationship between gut microbiota and ghrelin concentrations in patients with H pylori infection who received eradication therapy with antibiotics. The study compared patients with H pylori infection (n=40) with otherwise healthy patients with antigen-negative H pylori infection (n=20). Both patient groups received treatment with omeprazole 20 mg, clarithromycin 500 mg, and amoxicillin 1000 mg twice daily for 10 days. Patients with positive H pylori infection were evaluated at 2 clinical visits, prior to and 2 months after eradication therapy, and those with antigen-negative H pylori infection were evaluated at 1 clinical visit. For both patient groups, the clinical visits included physical examinations, collection of fasting blood glucose samples, and fasting blood glucose tolerance testing after administration of a 75 g bolus of oral glucose. The investigators evaluated the clinical, anthropometric, and dietary variables of patients with positive H pylori infection, as well as their fecal bacterial microbiota composition via 16S rRNA amplicon sequencing.
Among both patient groups, no significant differences were noted in regard to BMI, waist circumference, plasma glucose, plasma insulin, or triglycerides. Following eradication therapy, both patients had significantly increased HDL cholesterol (P =.021) and glucogen-like peptide 1 (P <.001) concentrations after eradication therapy; however, patients with positive H pylori infection had increased LDL cholesterol concentrations compared with those with antigen-negative H pylori infection (P =.036).
Compared with patients with antigen-negative H pylori infection, eradication therapy significantly decreased ghrelin concentrations among those with positive H pylori infection levels decreased significantly in H pylori patients after eradication therapy (P =.017) and as compared with controls (P =.04 vs P =.017, respectively). After undergoing oral glucose tolerance testing and eradication therapy, the area under the curve (AUC) of ghrelin decreased among patients in both groups (P =.03). Of note, ghrelin concentrations remained significantly decreased among patients with positive H pylori infection compared with those with antigen-negative H pylori infection 120 minutes after administration of a 75 g bolus of oral glucose (P =.039).
The investigators observed a linear correlation between specific gut microbiota and fasting ghrelin concentrations. RSO45 (P =.015), Bacteroides (P =.027), Bifidobacterium longum (P =.010), and Parabacteroides distasonis (P =.044) predicted positively fasting ghrelin concentrations, and Prevotellaceae (P =.011) predicted negatively fasting ghrelin concentrations. In addition, there was a significant positive correlation between postmeal (defined as 120 minutes after the ingestion of a 75 g bolus of glucose) ghrelin concentrations and Streptococcus, Bacteroides ovatus, and RSO45, and a significant negative correlation between postmeal ghrelin concentrations and Bacteroides coprophilus and Megasphaera.
The investigators also observed that changes in the abundance of specific bacteria were correlated with changes in the AUC of ghrelin among both patient groups after eradication therapy. In addition, there was an inverse correlation between the AUC of ghrelin and the presence of Lachnospiraceae (P =.008), Blautia (P =.001), and P stercorea (P =.017). Changes in the abundance of Megasphaera were associated with post eradication therapy fasting ghrelin concentrations (P =.02).
Although it is known that H pylori infection and its eradication therapy cause an imbalance in the gut microbiome, this study highlighted “how these disturbances are able to influence host metabolism” via alterations in ghrelin concentrations, the investigators concluded.
Martin-Nuñez GM, Cornejo-Pareja I, Clemente-Postigo M, Tinahones FJ, Moreno-Indias I. Helicobacter pylori eradication therapy affect the gut microbiota and ghrelin levels. Front Med. Published online August 12, 2021. doi:10.3389/fmed.2021.712908