PUMA-mediated epithelial cell apoptosis promotes Helicobacter pylori infection-mediated gastritis

Cell Death Dis. 2020 Feb 20;11(2):139. doi: 10.1038/s41419-020-2339-x.

Abstract

The molecular mechanism responsible for Helicobacter pylori infection-mediated gastritis and carcinogenesis is not yet clear. Increased evidence suggests that chronic gastritis and elevated gastric epithelial cell (GEC) apoptosis are crucial events during stomach carcinoma transformation. PUMA is a potent proapoptotic Bcl-2 protein and mediates acute tissue injury. In this study, we aimed to investigate the role of PUMA in GEC apoptosis and inflammation induced by H. pylori infection. As a result, we found that PUMA expression was elevated in gastritis tissues compared with uninvolved tissues, and it was correlated with the severity of apoptosis and gastritis. In mice, PUMA mRNA and protein were markedly induced in GECs upon induction of gastritis by H. pylori. PUMA-deficient mice were highly resistant to apoptosis and gastritis induced by H. pylori. Furthermore, the transcription factor NF-κB p65 binds to PUMA promoter to activate PUMA transcription after H. pylori infection. In addition, NF-κB inhibitor could rescue H. pylori-induced apoptosis and gastritis. Finally, H. pylori-induced activation of p-p65 and PUMA was mediated via Toll-like receptor 2 (TLR2) and blocked in TLR2 knockout mice. Taken together, these results verified the pro-inflammatory effect of PUMA in H. pylori-infected gastric tissue. Moreover, TLR2/NF-κB-mediated transcriptional regulation of PUMA contributes to the pathogenesis of H. pylori-infected gastritis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis Regulatory Proteins / deficiency
  • Apoptosis Regulatory Proteins / genetics
  • Apoptosis Regulatory Proteins / metabolism*
  • Apoptosis*
  • Cell Line, Tumor
  • Disease Models, Animal
  • Epithelial Cells / metabolism*
  • Epithelial Cells / microbiology
  • Epithelial Cells / pathology
  • Gastric Mucosa / metabolism*
  • Gastric Mucosa / microbiology
  • Gastric Mucosa / pathology
  • Gastritis / genetics
  • Gastritis / metabolism*
  • Gastritis / microbiology
  • Gastritis / pathology
  • Helicobacter Infections / genetics
  • Helicobacter Infections / metabolism*
  • Helicobacter Infections / microbiology
  • Helicobacter Infections / pathology
  • Helicobacter pylori / pathogenicity*
  • Humans
  • Mice, 129 Strain
  • Mice, Inbred C57BL
  • Mice, Knockout
  • NF-kappa B / metabolism
  • Proto-Oncogene Proteins / deficiency
  • Proto-Oncogene Proteins / genetics
  • Proto-Oncogene Proteins / metabolism*
  • Signal Transduction
  • Toll-Like Receptor 2 / genetics
  • Toll-Like Receptor 2 / metabolism
  • Tumor Suppressor Proteins / deficiency
  • Tumor Suppressor Proteins / genetics
  • Tumor Suppressor Proteins / metabolism*

Substances

  • Apoptosis Regulatory Proteins
  • BBC3 protein, human
  • NF-kappa B
  • PUMA protein, mouse
  • Proto-Oncogene Proteins
  • TLR2 protein, human
  • Tlr2 protein, mouse
  • Toll-Like Receptor 2
  • Tumor Suppressor Proteins