title: Restoration of heat shock protein70 suppresses gastric mucosal inducible nitric oxide synthase expression induced by Helicobacter pylori.
abstract: Heat shock proteins (HSPs) are crucial for the maintenance of cell integrity during normal cellular growth as well as during pathophysiological conditions. While functioning mainly as molecular chaperones, HSPs also appear to be involved in diverse biological activities, such as apoptosis, carcinogenesis, and cytoprotection from cytotoxic damage. Infection with Helicobacter pylori causes inflammation in the gastric mucosa, leading to gastritis, gastric ulcers, duodenal ulcer disease, and even gastric cancer, but the role of HSPs in H. pylori-associated gastropathy is not known. Using two-dimensional electrophoretic analysis, we have observed significant shifts in HSP profiles after H. pylori infection in RGM-1 cells. We therefore evaluated the effect of treatments that induce HSPs on H. pylori-induced inducible nitric oxide synthase (iNOS) expression. We found that H. pylori infection significantly attenuated the expression of HSP70, whereas exposure of cells to noncytotoxic heat shock or geranylgeranylacetone restored HSP70 expression, as well as suppressing the expression of iNOS, a major cause of H. pylori-induced gastric tissue damage. Our results suggest that induction of HSP70 confers cytoprotection against H. pylori infection by inhibiting the expression of iNOS. In conclusion, these results provide important insights into the flux in HSPs profiles in response to H. pylori infection and highlight the cytoprotective role of HSP70 in H. pylori infection.
authors.affiliation: Genomic Research Center for Gastroenterology, Ajou University School of Medicine, Suwon, Korea.
authors.forename: Marie
authors.initials: M
authors.lastname: Yeo
authors.forename: Hyun-kyung
authors.initials: HK
authors.lastname: Park
authors.forename: Dong-Kyu
authors.initials: DK
authors.lastname: Kim
authors.forename: Sung Won
authors.initials: SW
authors.lastname: Cho
authors.forename: Young Suk
authors.initials: YS
authors.lastname: Kim
authors.forename: Sang Yun
authors.initials: SY
authors.lastname: Cho
authors.forename: Young-ki
authors.initials: YK
authors.lastname: Paik
authors.forename: Ki-Baik
authors.initials: KB
authors.lastname: Hahm
mesh_terms: D000818:Animals; D015180:Electrophoresis, Gel, Two-Dimensional; D005753:Gastric Mucosa / Q000201:enzymology / Q000378:metabolism*; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism*; D016481:Helicobacter Infections / Q000378:metabolism*; D016480:Helicobacter pylori / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000235:genetics / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II; D051381:Rats
chemical_list: D018840:HSP70 Heat-Shock Proteins; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496318:Nos2 protein, rat