title: NaCl pretreatment attenuates H.pylori-induced DNA damage and exacerbates proliferation of gastric epithelial cells (GES-1).
abstract: BACKGROUND
  Both H. pylori infection and high salt (NaCl) diet are risks of gastric cancer, however, the interaction pattern of the two is not very clear. Our objective was to investigate the effects of NaCl-pretreated H. pylori on DNA damage and proliferation of gastric epithelial cell (GES-1).
  
  
  METHODS
  GES-1 cells were co-cultured with H.pylori or NaCl-pretreated H. pylori (with 30% NaCl) for 24 h. The morphological changes of all cells were observed by inverted phase contrast microscopy and transmission electron microscopy. Oxidative DNA damage was examined by immunofluorescence. Alterations in mitochondrial membrane potential and apoptosis rate were detected by flow cytometry and western blot, and expression of Ki-67, PCNA and P21 were evaluated using the immunocytochemical staining.
  
  
  RESULTS
  GES-1 cells co-cultured with NaCl-pretreated H.pylori exhibited morphological changes and oxidative DNA damage. Although no significant disruption of the mitochondrial membrane potential (ΔΨm) and apoptotic rate were observed compared with control groups, there were significant decreased in Bax and Caspase3 proteins and increased in Bcl-2 protein in GES-1 cells infected with H. pylori (30) when compared with GES-1 cells cultured with H. pylori. In addition, we found a proliferative effect on GES-1 cells with an increased expression of Ki-67 and PCNA as well as a decreased p21 expression, through which the cells may acquire the potential for malignant transformation.
  
  
  CONCLUSIONS
  NaCl-pretreated H. pylori possessed the ability to cause cell injury and promote proliferation in gastric epithelial cells.
authors: Radiation oncology Department of General Hospital of Shenyang Military Command, Shenyang, l10016 China.
authors: Ying
authors: Y
authors: Xu
authors: Radiation oncology Department of General Hospital of Shenyang Military Command, Shenyang, l10016 China.
authors: Ying
authors: Y
authors: Yan
authors: Emergency Medicine Department of General Hospital of Shenyang Military Command, Laboratory of Rescue Center of Severe Wound and Trauma PLA, 83 Wenhua Road, Shenhe District, Shenyang, l10016 China.
authors: Ming-Xiao
authors: MX
authors: Hou
authors: Emergency Medicine Department of General Hospital of Shenyang Military Command, Laboratory of Rescue Center of Severe Wound and Trauma PLA, 83 Wenhua Road, Shenhe District, Shenyang, l10016 China.
authors: Yun-En
authors: YE
authors: Liu
keywords: Apoptosis; Gastric epithelial cells; H. pylori; NaCl-pretreatment; Proliferation