PT  - JOURNAL ARTICLE
AU  - Tomohisa Takagi
AU  - Yuji Naito
AU  - Hitomi Okada
AU  - Takeshi Ishii
AU  - Katsura Mizushima
AU  - Satomi Akagiri
AU  - Satoko Adachi
AU  - Osamu Handa
AU  - Satoshi Kokura
AU  - Hiroshi Ichikawa
AU  - Ken Itoh
AU  - Masayuki Yamamoto
AU  - Hirofumi Matsui
AU  - Toshikazu Yoshikawa
TI  - Lansoprazole, a Proton Pump Inhibitor, Mediates Anti-Inflammatory Effect in Gastric Mucosal Cells through the Induction of Heme Oxygenase-1 via Activation of NF-E2-Related Factor 2 and Oxidation of Kelch-Like ECH-Associating Protein 1
AID  - 10.1124/jpet.109.152702
DP  - 2009 Oct 01
TA  - Journal of Pharmacology and Experimental Therapeutics
PG  - 255--264
VI  - 331
IP  - 1
4099  - http://jpet.aspetjournals.org/content/331/1/255.short
4100  - http://jpet.aspetjournals.org/content/331/1/255.full
SO  - J Pharmacol Exp Ther2009 Oct 01; 331
AB  - Induction of heme oxygenase-1 (HO-1) expression has been associated with cytoprotective and anti-inflammatory actions of lansoprazole, a proton pump inhibitor, but the underlying molecular mechanisms remain largely unresolved. In this study, we investigate the role of transcriptional NF-E2-related factor 2 (Nrf2), its phosphorylation/activation, and oxidation of Kelch-like ECH-associating protein 1 (Keap1) in lansoprazole-induced HO-1 up-regulation using cultured gastric epithelial cells (rat gastric mucosal cell line, RGM-1). HO-1 expression of RGM-1 cells was markedly enhanced in a time- and dose-dependent manner by the treatment with lansoprazole, and this up-regulation of HO-1 contributed to the inhibition of chemokine production from stimulated RGM-1 cells. Transfection of Nrf2-siRNA suppressed the lansoprazole-induced HO-1. An electrophoretic mobility shift assay showed increases in the nuclear translocation and stress-response elements (StRE) binding activity of Nrf2 proteins in RGM-1 cells treated with lansoprazole. Furthermore, in RGM-1 cells transfected with HO-1 enhancer luciferase reporter plasmid containing mutant StRE, lansoprazole-induced HO-1 reporter gene activity was diminished. Lansoprazole promoted the phosphorylation of extracellular signal-regulated kinase (ERK), and lansoprazole-induced HO-1 up-regulation was suppressed by U0126, an ERK-specific inhibitor. Phosphorylated Nrf2 protein was detected in the phosphoprotein fraction purified by a Pro-Q Diamond Phosphoprotein Enrichment kit. Finally, an oxidative form of the Keap1 protein was detected in lansoprazole-treated RGM-1 cells by analyzing S-oxidized proteins using biotinylated cysteine as a molecular probe. These results indicate that lansoprazole up-regulates HO-1 expression in rat gastric epithelial cells, and the up-regulated HO-1 contributes to the anti-inflammatory effects of the drug. Phosphorylation of ERK and Nrf2, activation and nuclear translocation of Nrf2, and oxidation of Keap1 are all involved in the lansoprazole-induced HO-1 up-regulation. © 2009 by the American Society for Pharmacology and Experimental Therapeutics