scholarly journals Glutathione Peroxidase-1 Suppresses the Unfolded Protein Response upon Cigarette Smoke Exposure

2016 ◽  
Vol 2016 ◽  
pp. 1-16 ◽  
Author(s):  
Patrick Geraghty ◽  
Nathalie Baumlin ◽  
Matthias A. Salathe ◽  
Robert F. Foronjy ◽  
Jeanine M. D’Armiento
Keyword(s):  
Oxidative Stress ◽  
Glutathione Peroxidase ◽  
Er Stress ◽  
Cigarette Smoke ◽  
Smoke Exposure ◽  
Cigarette Smoke Exposure ◽  
Glutathione Peroxidase 1 ◽  
Unfolded Protein ◽  
Stress Markers ◽  
Protein Response

Oxidative stress provokes endoplasmic reticulum (ER) stress-induced unfolded protein response (UPR) in the lungs of chronic obstructive pulmonary (COPD) subjects. The antioxidant, glutathione peroxidase-1 (GPx-1), counters oxidative stress induced by cigarette smoke exposure. Here, we investigate whether GPx-1 expression deters the UPR following exposure to cigarette smoke. Expression of ER stress markers was investigated in fully differentiated normal human bronchial epithelial (NHBE) cells isolated from nonsmoking, smoking, and COPD donors and redifferentiated at the air liquid interface. NHBE cells from COPD donors expressed heightened ATF4, XBP1, GRP78, GRP94, EDEM1, and CHOP compared to cells from nonsmoking donors. These changes coincided with reduced GPx-1 expression. Reintroduction of GPx-1 into NHBE cells isolated from COPD donors reduced the UPR. To determine whether the loss of GPx-1 expression has a direct impact on these ER stress markers during smoke exposure,Gpx-1−/−mice were exposed to cigarette smoke for 1 year. Loss ofGpx-1expression enhanced cigarette smoke-induced ER stress and apoptosis. Equally, induction of ER stress with tunicamycin enhanced antioxidant expression in mouse precision-cut lung slices. Smoke inhalation also exacerbated the UPR response during respiratory syncytial virus infection. Therefore, ER stress may be an antioxidant-related pathophysiological event in COPD.

Comparison of Oxidative Effects of Electronic Cigarette and Tobacco Smoke Exposure Performed Experimentally

2021 ◽  
pp. 1-7
Author(s):  
Oktay Aslaner
Keyword(s):  
Oxidative Stress ◽  
Cigarette Smoke ◽  
Tobacco Smoke ◽  
Smoke Exposure ◽  
Electronic Cigarette ◽  
Tobacco Smoke Exposure ◽  
Cigarette Smoke Exposure ◽  
Control Group ◽  
Exposure Group ◽  
Oxidative Effects

<b><i>Objective:</i></b> Cigarette smoking is a life-threatening habit that has rapidly spread in every socioeconomic part of the public worldwide. There exist mechanisms of nicotine delivery available to use in the hope of halting cigarette smoking, and the electronic cigarette (EC) is one of the common methods used for tobacco smoking replacement. This study aimed to investigate experimentally the oxidative effects of tobacco smoke and EC smoke which contain nicotine. <b><i>Method:</i></b> We constructed smoke circuit rooms for exposing the rats to EC or tobacco smoke. Three groups were created, the control group (<i>N</i> = 8); the electronic cigarette group (<i>N</i> = 8), exposure to electronic cigarette smoke for 2 h per day; and the tobacco group (<i>N</i> = 8), exposure to traditional cigarette smoke for 2 h per day. After the first and second week of exposure, blood samples were obtained, and serum oxidative stress index (OSI), paraoxonase 1 (PON1) activity, and prolidase levels were evaluated. <b><i>Results:</i></b> Higher values of OSI and prolidase levels were detected in the first week of EC or tobacco smoke exposure in both study groups (<i>p</i> &#x3c; 0.001) when compared with the control group, and partial decrements were observed in the second week. By contrast, elevated PON1 levels were observed in the second week after EC or tobacco smoke exposure. The highest OSI levels were observed in the tobacco smoke group (<i>p</i> &#x3c; 0.001). The lowest values of PON1 levels were detected in the first week of the electronic cigarette smoke group, and this decremental value was statistically different than normal, the second week of the electronic cigarette smoke group, the first week of the traditional cigarette smoke exposure group, and the second week of the traditional cigarette smoke exposure group values (<i>p</i> &#x3c; 0.000). <b><i>Conclusion:</i></b> Our results indicate that EC smoke induced oxidative stress. Therefore, ECs are potentially risky for human health and can lead to important health problems.

scholarly journals Impact of maternal cigarette smoke exposure on brain inflammation and oxidative stress in male mice offspring

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Yik Lung Chan ◽  
Sonia Saad ◽  
Carol Pollock ◽  
Brian Oliver ◽  
Ibrahim Al-Odat ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cigarette Smoke ◽  
Smoke Exposure ◽  
Brain Inflammation ◽  
Cigarette Smoke Exposure ◽  
Male Mice ◽  
And Oxidative Stress

scholarly journals Impact of acute exposure to cigarette smoke on airway gene expression

2018 ◽  
Vol 50 (9) ◽  
pp. 705-713 ◽  
Author(s):  
E. Billatos ◽  
A. Faiz ◽  
Y. Gesthalter ◽  
A. LeClerc ◽  
Y. O. Alekseyev ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Gene Expression ◽  
Lung Cancer ◽  
Cigarette Smoke ◽  
Smoke Exposure ◽  
Acute Exposure ◽  
Cigarette Smoke Exposure ◽  
Airway Epithelial ◽  
Long Term Effects ◽  
Chronic Smoking

Background: Understanding effects of acute smoke exposure (ASE) on airway epithelial gene expression and their relationship with the effects of chronic smoke exposure may provide biological insights into the development of smoking-related respiratory diseases. Methods: Bronchial airway epithelial cell brushings were collected from 63 individuals without recent cigarette smoke exposure and before and 24 h after smoking three cigarettes. RNA from these samples was profiled on Affymetrix Human Gene 1.0 ST microarrays. Results: We identified 91 genes differentially expressed 24 h after ASE (false discovery rate < 0.25). ASE induced genes involved in xenobiotic metabolism, oxidative stress, and inflammation and repressed genes related to cilium morphogenesis and cell cycle. While many genes altered by ASE are altered similarly in chronic smokers, metallothionein genes are induced by ASE and suppressed in chronic smokers. Metallothioneins are also suppressed in current and former smokers with lung cancer relative to those without lung cancer. Conclusions: Acute exposure to as little as three cigarettes and chronic smoking induce largely concordant changes in airway epithelial gene expression. Differences in short-term and long-term effects of smoking on metallothionein expression and their relationship to lung cancer requires further study given these enzymes’ role in the oxidative stress response.

scholarly journals Transcription factor ATF4 directs basal and stress-induced gene expression in the unfolded protein response and cholesterol metabolism in the liver

2016 ◽  
Vol 27 (9) ◽  
pp. 1536-1551 ◽  
Author(s):  
Michael E. Fusakio ◽  
Jeffrey A. Willy ◽  
Yongping Wang ◽  
Emily T. Mirek ◽  
Rana J. T. Al Baghdadi ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Gene Expression ◽  
Transcription Factor ◽  
Er Stress ◽  
Unfolded Protein Response ◽  
Cholesterol Metabolism ◽  
Unfolded Protein ◽  
Expression Of Genes ◽  
The Unfolded Protein Response ◽  
Protein Response

Disturbances in protein folding and membrane compositions in the endoplasmic reticulum (ER) elicit the unfolded protein response (UPR). Each of three UPR sensory proteins—PERK (PEK/EIF2AK3), IRE1, and ATF6—is activated by ER stress. PERK phosphorylation of eIF2 represses global protein synthesis, lowering influx of nascent polypeptides into the stressed ER, coincident with preferential translation of ATF4 (CREB2). In cultured cells, ATF4 induces transcriptional expression of genes directed by the PERK arm of the UPR, including genes involved in amino acid metabolism, resistance to oxidative stress, and the proapoptotic transcription factor CHOP (GADD153/DDIT3). In this study, we characterize whole-body and tissue-specific ATF4-knockout mice and show in liver exposed to ER stress that ATF4 is not required for CHOP expression, but instead ATF6 is a primary inducer. RNA-Seq analysis indicates that ATF4 is responsible for a small portion of the PERK-dependent UPR genes and reveals a requirement for expression of ATF4 for expression of genes involved in oxidative stress response basally and cholesterol metabolism both basally and under stress. Consistent with this pattern of gene expression, loss of ATF4 resulted in enhanced oxidative damage, and increased free cholesterol in liver under stress accompanied by lowered cholesterol in sera.

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