Abstract
Chronic Helicobacter pylori infection is a major contributor to gastric disease progression, with its involvement in autophagy and stem cell dynamics playing a critical role in disease mechanisms. This study investigated how H. pylori, particularly in combination with the carcinogen N-nitroso-N-methylurea (NMU), disrupted autophagy and stem cell function, driving gastric pathology. H. pylori infection significantly increased autophagy, promoted the epithelial-mesenchymal transition, suppressed Tff2 and Ghrelin expression in mouse gastric organoids, and enhanced stem cell proliferation (organoid numbers increased 92% compared to control at 24 weeks, p < 0.001), while NMU caused milder autophagy, severe inflammation, glandular dilation, and reduced stemness markers (CD133 decreased 30% at 24 weeks, p < 0.05). Combined H. pylori and NMU exposure synergistically dysregulated Tff2/Ghrelin expression, exacerbated autophagic flux disruption, and impaired stem cell function, reducing organoid budding (decreased 43% vs. H. pylori alone at 36 weeks, p < 0.01) and dysregulating CD133, CD44, Lgr5, and SOX2 expression. Pathologically, this combination led to severe gastric damage, including intestinal metaplasia and neutrophil infiltration. Chloroquine (CQ) treatment mitigates these effects by reversing autophagic dysfunction, restoring stem cell capacity (Lgr5 increased 97% at 44 weeks, p < 0.05), differentially modulating Tff2/Ghrelin: potentiating Tff2 and suppressing Ghrelin, normalizing organoid growth, attenuating the EMT, and reducing inflammation, particularly in the H. pylori + NMU group. These findings elucidate how H. pylori and NMU drive gastric pathology through autophagy-stem cell crosstalk and highlight CQ's potential as a targeted therapeutic strategy for infection-associated gastric damage.