Adaptive HNE-Nrf2-HO-1 pathway against oxidative stress is associated with acute gastric mucosal lesions.
Disturbance of the microcirculation and generation of reactive oxygen species are crucial in producing acute gastric mucosal lesions (AGML). To understand the protective mechanism against mucosal injury and oxidative stress in the stomach, we investigated sequential expression and localization of a product of lipid peroxidation and a chemical mediator of the oxidative response array, 4-hydroxynonenal (HNE), transcriptional factor, NF-E2-related factor (Nrf2), and the inducible heme oxygenase (HO-1) in the injured stomach. AGML was produced by intragastric administration of 0.6 N HCl in male rats. Expression and localization of HNE, Nrf2, and HO-1 were investigated by Western blotting, immunohistochemistry, real-time RT-PCR, and in situ hybridization histochemistry. Mucosal lesions and expression of HNE and HO-1 were assessed by prior treatment with the PGI2 analog beraprast or after sensory denervation by pretreatment with capsaicin. Mucosal lesions were assessed by prior treatment with a HO-1 inhibitor, zinc protoporphyrin (ZnPP). After AGML, increased generation of HNE was observed in the injured mucosa and the surrounding submucosa, followed by nuclear translocation of Nrf2 and upregulation of HO-1 in the macrophages located in the margin of the injured mucosa and in the submucosa. Pretreatment with beraprost attenuated AGML and downregulated the expression of HNE and HO-1, while sensory denervation aggravated AGML and upregulated the expression of HNE and HO-1. Pretreatment with ZnPP also aggravated AGML. The sequential HNE-Nrf2-HO-1 pathway in the gastric mucosal cells and the macrophages is involved in an adaptive mechanism against oxidative stress after AGML.
Ueda
Kazuki
K
Second Department of Internal Medicine, Wakayama Medical University, 811-1 Kimiidera, Wakayama City 641-8509, Japan.
Ueyama
Takashi
T
Yoshida
Ken-ichi
K
Kimura
Hiroko
H
Ito
Takao
T
Shimizu
Yasuhito
Y
Oka
Masashi
M
Tsuruo
Yoshihiro
Y
Ichinose
Masao
M
D000222:Adaptation, Physiological; D000447:Aldehydes / Q000378:metabolism*; D000818:Animals; D002211:Capsaicin / Q000494:pharmacology; D019610:Cytoprotection; D003714:Denervation; D004195:Disease Models, Animal; D004791:Enzyme Inhibitors / Q000494:pharmacology; D011464:Epoprostenol / Q000031:analogs & derivatives / Q000494:pharmacology; D005753:Gastric Mucosa / Q000187:drug effects / Q000201:enzymology* / Q000294:innervation / Q000473:pathology; D006419:Heme Oxygenase (Decyclizing) / Q000037:antagonists & inhibitors / Q000378:metabolism*; D006851:Hydrochloric Acid; D015227:Lipid Peroxidation; D008264:Macrophages / Q000201:enzymology; D008297:Male; D051267:NF-E2-Related Factor 2 / Q000378:metabolism*; D018384:Oxidative Stress / Q000187:drug effects; D011524:Protoporphyrins / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D015398:Signal Transduction / Q000187:drug effects; D013276:Stomach Ulcer / Q000139:chemically induced / Q000201:enzymology* / Q000473:pathology / Q000517:prevention & control*
D000447:Aldehydes; D004791:Enzyme Inhibitors; D051267:NF-E2-Related Factor 2; D011524:Protoporphyrins; C017803:zinc protoporphyrin; C048081:beraprost; D011464:Epoprostenol; D006419:Heme Oxygenase (Decyclizing); C491523:Hmox1 protein, rat; C027576:4-hydroxy-2-nonenal; D006851:Hydrochloric Acid; D002211:Capsaicin