Effect of Helicobacter pylori infection on autophagy and apoptosis of gastric epithelial cells

Objective:To investigate the effects of Helicobacter pylori(Hp) on autophagy and apoptosis of gastric epithelial cells.Methods:Human gastric epithelial cell line GES-1(GES-1) were infected by Hp in vitro culture,the intervention groups of Hp-infected GES-1 were treated with autophagy inducer-rapamycin(RAPA) and autophagy inhibitor-3-methyladenine(3-MA),and uninfected cell was set as the blank control group.Cells were collected at 2,4,6,12 and 24 h after infection.The effects of Hp infection on autophagy and apoptosis of GES-1 were observed by Western Blotting,fluorescent staining,transmission electron microscopy,flow cytometry and intracellular bacterial survival counting.Results:Autophagy marker protein microtubule associated protein 1 light chain 3-Ⅱ expression and cellular autophagy fluorescent particles were found at 2 h after treatment,the typical autophagic vacuoles with double or multilayer membrane in the cytoplasm were observed by transmission electron microscopy.Autophagy of infected cells peaked at 4 h,gradually decreased and disappeared.Autophagy of RAPA-treated cells infected by Hp further enhanced,while the apoptotic rate and intracellular bacterial survival were lower than those in RAPA-untreated infected cells(PPPConclusions:Hp can induce the autophagy in gastric epithelial cells in the early infection.The autophagy inducer-RAPA and autophagy inhibitor-3-MA can promote or reduce the autophagy in Hp-infected cells,which can lessen or enhance injury of infected cells.