Enhancement of cytoprotective ability and cell restoration in 70‐kDa heat shock protein gene‐transfected rat gastric mucosal cells

Summary Background Many recent studies have indicated the importance of heat shock proteins for cell survival under stress conditions. Some heat shock proteins are known to be involved in cytoprotection against environmental stresses, through their function as ‘molecular chaperones’. Aim To examine the biological characteristics of HSP70 gene‐transfected gastric mucosal cells. Materials and methods Complimentary DNA of human HSP70 gene was transfected to RGM‐1 cells (rat gastric mucosal cell line) and HSP70 highly‐expressing cells were selected and cloned. A single clone (7018‐RGM‐1), which highly expressed HSP70 compared with RGM‐1, was used in this study. Cytoprotective ability against H2O2 or ethanol was analysed by WST‐assay and LDH‐release. Wound restoration of artificially created wounds was also compared between RGM‐1 and 7018‐RGM‐1 cells. Results We successfully cloned HSP70 highly‐expressing gastric mucosal cells, which expressed a level of HSP70 equal to 350% of that of RGM‐1 cells. Over‐expression of HSP70 clearly enhanced cytoprotective ability against H2O2 or ethanol‐induced cell damage. Wound restoration was enhanced in 7018‐RGM‐1 cells compared with RGM‐1 cells. Conclusion Our results suggested that expression of HSP70 might play important roles not only in cytoprotection but also in mucosal wound restoration, mediated by the molecular chaperone function of HSP70.