PT  - JOURNAL ARTICLE
AU  - Ken-ichiro Tanaka
AU  - Shinji Tsutsumi
AU  - Yasuhiro Arai
AU  - Tatsuya Hoshino
AU  - Keitarou Suzuki
AU  - Eiichi Takaki
AU  - Takaaki Ito
AU  - Koji Takeuchi
AU  - Akira Nakai
AU  - Tohru Mizushima
TI  - Genetic Evidence for a Protective Role of Heat Shock Factor 1 against Irritant-Induced Gastric Lesions
AID  - 10.1124/mol.106.033282
DP  - 2007 Apr 01
TA  - Molecular Pharmacology
PG  - 985--993
VI  - 71
IP  - 4
4099  - http://molpharm.aspetjournals.org/content/71/4/985.short
4100  - http://molpharm.aspetjournals.org/content/71/4/985.full
SO  - Mol Pharmacol2007 Apr 01; 71
AB  - Gastric lesions result from an imbalance between aggressive and defensive factors. Indirect lines of evidence suggest that heat shock proteins (HSPs) induced by various aggressive factors provide a major protective mechanism. In this study, we compared gastric ulcerogenic response in wild-type mice and in those lacking heat shock factor 1 (HSF1), a transcription factor for hsp genes. The severity of gastric lesions induced by ethanol or hydrochloric acid was worsened in HSF1-null mice. Immunoblotting, real-time reverse transcription-polymerase chain reaction, immunohistochemical analysis, and terminal deoxynucleotidyl transferase dUTP nick-end labeling assay revealed that the ethanol administration up-regulated gastric mucosal HSPs, in particular HSP70, in an HSF1-dependent manner, and more apoptotic cells were observed in the gastric mucosa of HSF1-null mice than in wild-type mice. In contrast, other parameters governing the gastric ulcerogenic response, including gastric acid secretion, gastric mucosal blood flow, and prostaglandin E2 levels, were not significantly affected by the absence of the hsf1 gene. Geranylgeranylacetone (GGA), a clinically used antiulcer drug with HSP-inducing activity, suppressed ethanol-induced gastric lesions in wild-type mice but not in heat shock factor 1 (HSF1)-null mice. The results suggest that the aggravation of irritant-induced gastric lesions in HSF1-null mice is due to their inability to up-regulate HSPs, leading to apoptosis. It is also suggested that the HSP-inducing activity of GGA contributes to the drug's antiulcer activity. This study provides direct genetic evidence that HSPs, after their HSF1-dependent up-regulation, confer gastric protection against the irritant-induced lesions. The American Society for Pharmacology and Experimental Therapeutics