Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0242706 (hyperoxia)
 5,219 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In this study, we have used the rat model of hyperoxia to examine the molecular responses to oxidative stress in lung. We show that in addition to the antioxidant enzyme manganese superoxide dismutase, expression of a variety of stress-responsive genes including heme oxygenase-1, c-fos, c-jun, CAAT-enhancer binding protein (C/EBP)-beta, and C/EBP-delta were increased after hyperoxia. Increased c-fos, c-jun, C/EBP-beta, and C/EBP-delta mRNA expression was correlated with increased DNA binding activity of the transcription factor complexes activator protein 1 and C/EBP in tissue lysates. Because oxidative damage plays an important role in the aging process and little is known about the susceptibility of aged rats to hyperoxia, we also examined the relative tolerance of old rats to hyperoxia. Surprisingly, we observed that aged rats exhibit greater tolerance to hyperoxic stress than young rats. Old rats exhibited decreased arterial oxygen tension when compared to young rats after hyperoxia exposure. This increased tolerance coincided with decreased albumin levels in bronchoalveolar lavage and the delayed onset of activation of transcription factors and expression of oxidative stress-inducible genes in old rats. Transcription factor and stress-response gene activation may serve as useful molecular markers for oxidant lung injury.
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PMID:Molecular responses to hyperoxia in vivo: relationship to increased tolerance in aged rats. 759 40

The Clara cell secretory protein (CCSP) imparts a protective effect to the lung during oxidant injury. However, exposure to supplemental oxygen, a common therapeutic modality for lung disease, represses the expression of CCSP in the adult mouse lung. We investigated the mechanisms of hyperoxia-induced repression of the mouse CCSP promoter. Deletion experiments in vivo and in vitro indicated that the hyperoxia-responsive elements are localized to the proximal -166 bp of the CCSP promoter. Electrophoretic mobility shift and supershift analyses demonstrated increased binding of c-Jun at the activator protein-1 site, increased binding of CCAAT/enhancer binding protein (C/EBP) beta at the C/EBP sites, and decreased binding at the Nkx2.1 sites. Western analyses revealed that hyperoxia exposure induced an increase in the expression of the C/EBPbeta isoform liver-inhibiting protein (LIP) and an increase in cytoplasmic Nkx2.1. Cotransfection of LIP or c-Jun expression plasmids decreased the transcriptional activity of the proximal -166-bp CCSP promoter. These observations suggest that hyperoxia-induced repression of the CCSP gene is mediated, at least in part, at the level of transcription and that multiple mechanisms mediate this repression. Moreover, these novel observations may provide insights for generation of therapeutic interventions for the amelioration of oxidant-induced lung injury.
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PMID:Multiple mechanisms for oxygen-induced regulation of the Clara cell secretory protein gene. 1450 May 49

In mammals, disulfide isomerase associated 3, PDIA3, is a member of the endoplasmic reticulum (ER) stress proteins, which can be induced by oxidative stress; however, its role in relation to stress regulation is still unknown in fish. Here, we report the cloning of a coding region of PDIA3 from the Atlantic salmon. PDIA3 mRNA expression was evaluated in the liver of Atlantic salmon exposed to environmental hyperoxia stress and toxic perfluorooctane sulfonate (PFOS) exposure stress. The PDIA3 sequence contained two PDI-typical thioredoxin active sites of WCGHC and shared approximately 70% identity with mammalian PDIA3, and its mRNA was primarily expressed in the liver. PDIA3 was significantly increased in the liver of Atlantic salmon exposed to hyperoxic water during smoltification. Also Mn superoxide dismutase (Mn-SOD) and CCAAT/enhancer binding protein (C/EBP), other markers of oxidative stress, were upregulated by hyperoxia. Furthermore, PFOS exposure of hepatocytes resulted in elevated mRNA expression of PDIA3, Mn-SOD and C/EBPdelta as well as peroxisome proliferator-activated receptor gamma (PPARgamma). These results indicate a signaling connection between oxidative stress and ER stress. PDIA3 and C/EBPdelta may be valuable markers in fish for exposure and effect to environmental stress.
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PMID:Stress-induced expression of protein disulfide isomerase associated 3 (PDIA3) in Atlantic salmon (Salmo salar L.). 1974 60