Gene expression profiles on hypoxia and reoxygenation in rat gastric epithelial cells: A high-density DNA microarray analysis

Previous investigations have demonstrated that the cellular signaling induced by hypoxia-reoxygenation is a major pathway contributing to gastric mucosal injury induced by stress, non-steroidal anti-inflammatory drugs, and Helicobacter pylori. The aim of the present study was to perform a gene expression analysis of the gastric mucosal cellular response and to define the protective molecules in hypoxia and reoxygenation using a high-density DNA microarray analysis. Normal rat gastric mucosal (RGM-1) cells were subjected to hypoxia for 2 h, and reoxygenation was initiated by placing the cells in an environment of normoxia for 2, 4, or 8 h. Total RNA was extracted, and differences in the gene expression profiles between the normoxia and hypoxia groups or among the different durations of reoxygenation were investigated using a high-density DNA microarray. HIF-1- and apoptosis-related genes were modulated by hypoxia. Moreover, inflammation-, stress-, and wound-healing-related genes were regulated by reoxygenation following hypoxia. In particular, the expression of heat shock protein-70, amphiregulin and cyclooxygenase-2 were upregulated during reoxygenation following hypoxia, suggesting that these upregulations may play an important role in maintaining cell survival and supporting cell function. Copyright (c) 2006 S. Karger AG, Basel.