Peripheral miRNA-155 Expression and Circulating Inflammatory Cytokines in Patients with Helicobacter Pylori–Associated Chronic Gastritis: An Exploratory Case–Control Study

Background/Aims: Infection with Helicobacter pylori is the most common cause of chronic gastritis and has been linked to persistent inflammation of the stomach. miRNA-155 and inflammatory cytokines play crucial roles in immune regulation but their systemic profiles of expression are not fully understood in H. pylori–associated chronic gastritis. This pilot study was conducted to evaluate peripheral miRNA-155 expression accompanied by circulating levels of IL-6 IFN-γ and IL-10 in chronic gastritis H. pylori –related patients. Methods: Twenty-five patients with endoscopically and histologically diagnosed H. pylori–associated chronic gastritis and 25 age-matched healthy subjects were included in this study. The expression of miRNA-155 was determined in peripheral blood by using quantitative real-time PCR • Whereas the levels of serum cytokines were measured by ELISA. Group comparison and an exploratory association were carried out. Results: The H. pylori–associated chronic gastritis patients had significantly higher peripheral miRNA-155 levels compared with controls (p < 0.001). Serum IL-6 IFN-γ and IL-10 were all statistically higher in patients (all p < 0.001). Unadjusted logistic regression analyses showed significant correlations between biomarker levels and H.pylori infection status among the study population. Conclusion: This exploratory case–control study provides evidence of systemic perturbations in miRNA-155 expression and inflammatory cytokines in subjects with H. pylori–associated chronic gastritis. These data indicate immune-regulatory changes are related in whole blood and justify validation studies on additional cohorts. Due to the exploratory nature and small size of our cohort • The results need to be interpreted with caution and verified by independent cohorts.