Acute cigarette smoke exposure induces apoptosis of alveolar macrophages

2001 ◽  
Vol 281 (6) ◽  
pp. L1392-L1401 ◽  
Author(s):  
Kazutetsu Aoshiba ◽  
Jun Tamaoki ◽  
Atsushi Nagai
Keyword(s):  
Cigarette Smoke ◽  
Alveolar Macrophages ◽  
Critical Role ◽  
Light And Electron Microscopy ◽  
In Vivo Studies ◽  
Cigarette Smoke Exposure ◽  
Protein Accumulation ◽  
Cytochrome C Release ◽  
Bax Protein

Alveolar macrophages (AMs) may play a critical role in cigarette smoke (CS)-related pulmonary diseases. This study was designed to determine whether CS induces apoptosis of AMs. In in vitro studies, mouse, rat, and human AMs and human blood monocyte-derived macrophages cultured with aqueous whole CS extracts underwent apoptosis that was detected by light and electron microscopy and terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling. The gas phase of CSE did not cause apoptosis. The CS-induced apoptosis was associated with increased oxidative stress, Bax protein accumulation, mitochondrial dysfunction, and mitochondrial cytochrome c release but was independent of p53, Fas, and caspase activation. This apoptosis was inhibited by antioxidants such as glutathione, ascorbic acid, and α-tocopherol. In in vivo studies where rats were exposed to the smoke from 10 cigarettes over 5 h in an exposure chamber, ∼3% of AMs obtained by bronchoalveolar lavage after 24 h showed apoptosis. These results suggest that acute CS exposure is capable of inducing apoptosis of AMs.

Sphingosine kinase 1 regulates lysyl oxidase through STAT3 in hyperoxia-mediated neonatal lung injury

Thorax ◽  
2021 ◽  
pp. thoraxjnl-2020-216469
Author(s):  
Alison W Ha ◽  
Tao Bai ◽  
David L Ebenezer ◽  
Tanvi Sethi ◽  
Tara Sudhadevi ◽  
...  
Keyword(s):  
Lung Injury ◽  
Lysyl Oxidase ◽  
Critical Role ◽  
Sphingosine Kinase ◽  
In Vivo Studies ◽  
Sphingosine Kinase 1 ◽  
Neonatal Lung ◽  
Neonatal Lung Injury

IntroductionNeonatal lung injury as a consequence of hyperoxia (HO) therapy and ventilator care contribute to the development of bronchopulmonary dysplasia (BPD). Increased expression and activity of lysyl oxidase (LOX), a key enzyme that cross-links collagen, was associated with increased sphingosine kinase 1 (SPHK1) in human BPD. We, therefore, examined closely the link between LOX and SPHK1 in BPD.MethodThe enzyme expression of SPHK1 and LOX were assessed in lung tissues of human BPD using immunohistochemistry and quantified (Halo). In vivo studies were based on Sphk1−/− and matched wild type (WT) neonatal mice exposed to HO while treated with PF543, an inhibitor of SPHK1. In vitro mechanistic studies used human lung microvascular endothelial cells (HLMVECs).ResultsBoth SPHK1 and LOX expressions were increased in lungs of patients with BPD. Tracheal aspirates from patients with BPD had increased LOX, correlating with sphingosine-1-phosphate (S1P) levels. HO-induced increase of LOX in lungs were attenuated in both Sphk1−/− and PF543-treated WT mice, accompanied by reduced collagen staining (sirius red). PF543 reduced LOX activity in both bronchoalveolar lavage fluid and supernatant of HLMVECs following HO. In silico analysis revealed STAT3 as a potential transcriptional regulator of LOX. In HLMVECs, following HO, ChIP assay confirmed increased STAT3 binding to LOX promoter. SPHK1 inhibition reduced phosphorylation of STAT3. Antibody to S1P and siRNA against SPNS2, S1P receptor 1 (S1P1) and STAT3 reduced LOX expression.ConclusionHO-induced SPHK1/S1P signalling axis plays a critical role in transcriptional regulation of LOX expression via SPNS2, S1P1 and STAT3 in lung endothelium.

scholarly journals The Functional Role of Zinc Finger E Box-Binding Homeobox 2 (Zeb2) in Promoting Cardiac Fibroblast Activation

2018 ◽  
Vol 19 (10) ◽  
pp. 3207 ◽  
Author(s):  
Fahmida Jahan ◽  
Natalie Landry ◽  
Sunil Rattan ◽  
Ian Dixon ◽  
Jeffrey Wigle
Keyword(s):  
Smooth Muscle ◽  
Zinc Finger ◽  
Cardiac Fibrosis ◽  
Smooth Muscle Actin ◽  
Critical Role ◽  
Cardiac Fibroblast ◽  
In Vivo Studies ◽  
Fibroblast Activation ◽  
E Box

Following cardiac injury, fibroblasts are activated and are termed as myofibroblasts, and these cells are key players in extracellular matrix (ECM) remodeling and fibrosis, itself a primary contributor to heart failure. Nutraceuticals have been shown to blunt cardiac fibrosis in both in-vitro and in-vivo studies. However, nutraceuticals have had conflicting results in clinical trials, and there are no effective therapies currently available to specifically target cardiac fibrosis. We have previously shown that expression of the zinc finger E box-binding homeobox 2 (Zeb2) transcription factor increases as fibroblasts are activated. We now show that Zeb2 plays a critical role in fibroblast activation. Zeb2 overexpression in primary rat cardiac fibroblasts is associated with significantly increased expression of embryonic smooth muscle myosin heavy chain (SMemb), ED-A fibronectin and α-smooth muscle actin (α-SMA). We found that Zeb2 was highly expressed in activated myofibroblast nuclei but not in the nuclei of inactive fibroblasts. Moreover, ectopic Zeb2 expression in myofibroblasts resulted in a significantly less migratory phenotype with elevated contractility, which are characteristics of mature myofibroblasts. Knockdown of Zeb2 with siRNA in primary myofibroblasts did not alter the expression of myofibroblast markers, which may indicate that Zeb2 is functionally redundant with other profibrotic transcription factors. These findings add to our understanding of the contribution of Zeb2 to the mechanisms controlling cardiac fibroblast activation.

scholarly journals Punicalagin protects H9c2 cardiomyocytes from doxorubicin-induced toxicity through activation of Nrf2/HO-1 signaling

2019 ◽  
Vol 39 (5) ◽  
Author(s):  
Mingfang Ye ◽  
Linlin Zhang ◽  
Yuanming Yan ◽  
Huizhong Lin
Keyword(s):  
Wide Spectrum ◽  
Critical Role ◽  
Antitumor Agent ◽  
Cytochrome C Release ◽  
Beneficial Effects ◽  
H9c2 Cardiomyocytes ◽  
Underlying Mechanisms ◽  
Interfering Rna

Abstract Doxorubicin (DOX) is a wide-spectrum antitumor agent, but its clinical application is largely limited by its cardiotoxicity. Therefore, identification of effective agents against DOX-induced cardiotoxicity is of critical importance. The present study aimed to determine the beneficial role of punicalagin (PUN), a polyphenol isolated from pomegranate, in DOX-induced cardiotoxicity in vitro and explored the underlying mechanisms. H9c2 cardiomyocytes were pretreated with different concentrations (50, 100 and 200 μM) of PUN prior to DOX exposure. The results showed that PUN pretreatment significantly increased cell viability, inhibited lactate dehydrogenase (LDH) release and suppressed cell apoptosis induced by DOX. Additionally, PUN pretreatment attenuated the loss of mitochondrial membrane potential and cytochrome c release. Besides, PUN further enhanced the expression of nuclear Nrf2 and HO-1 in DOX-treated H9c2 cells, and the aforementioned beneficial effects of PUN were partially abolished by small interfering RNA (siRNA)-mediated Nrf2 knockdown. Hence, our findings clearly revealed that PUN might be a promising agent for alleviating the cardiotoxicity of DOX, and Nrf2/HO-1 signaling might serve a critical role during this process.

Humic-like substances in cigarette smoke condensate and lung tissue of smokers

1994 ◽  
Vol 266 (4) ◽  
pp. L382-L388 ◽  
Author(s):  
A. J. Ghio ◽  
J. Stonehuerner ◽  
D. R. Quigley
Keyword(s):  
Free Radical ◽  
Cigarette Smoke ◽  
Lung Tissue ◽  
Cigarette Smoke Exposure ◽  
Cigarette Smoke Condensate ◽  
Free Radical Generation ◽  
Carboxylate Content ◽  
Radical Generation

Deposition of pigmented matter in the lower respiratory tract correlates with the extent of emphysema in smokers as well as with free radical generation and iron accumulation. Pulmonary emphysema is postulated to be mediated by free radical generation which is either directly or indirectly associated with cigarette smoke exposure. The hypothesis was tested that 1) incomplete combustion of tobacco yields humic-like substances (HLS) which 2) deposit in the lung as pigmented particulates, 3) complex iron cations in vitro and in vivo, and 4) have a capacity to catalyze oxidant formation. HLS, isolated by alkali extraction of cigarette smoke condensate (CSC) (Tobacco Health Research Institute, University of Kentucky), demonstrated a high carbon and low carboxylate content on elemental and functional group analyses, respectively, compared with values for HLS sequestered from soils. The HLS isolated from CSC had a capacity to complex iron in vitro and accumulated the metal in vivo after intratracheal instillation in an animal model. Both HLS and its iron complex generated free radicals, and some portion of this oxidant generation was metal dependent. Lung tissue collected at autopsy from smokers contained HLS with an infrared spectrum almost identical to that of the material isolated from CSC. Associations between particulate deposition, metal accumulation, and free radical generation suggest a possible role of HLS in the induction of lung disease following cigarette exposure.

scholarly journals Lycopene Protects against Smoking-Induced Lung Cancer by Inducing Base Excision Repair

Antioxidants ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 643 ◽  
Author(s):  
Junrui Cheng ◽  
Baxter Miller ◽  
Emilio Balbuena ◽  
Abdulkerim Eroglu
Keyword(s):  
Oxidative Stress ◽  
Lung Cancer ◽  
Cigarette Smoke ◽  
Connexin 43 ◽  
Excision Repair ◽  
Critical Role ◽  
A549 Cells ◽  
Human Lung Cancer ◽  
Cigarette Smoke Exposure ◽  
Mrna Levels

Background: Oxidative stress plays a critical role in lung cancer progression. Carotenoids are efficient antioxidants. The objective of this study was to explore the efficacy of all-trans retinoic acid (ATRA) and carotenoids in cigarette smoke-induced oxidative stress within A549 human lung cancer epithelial cells. Methods: A549 cells were pretreated with 1-nM, 10-nM, 100-nM, 1-μM and 10-μM ATRA, β-carotene (BC) and lycopene for 24 h, followed by exposure to cigarette smoke using a smoking chamber. Results: The OxyBlot analysis showed that smoking significantly increased oxidative stress, which was inhibited by lycopene at 1 nM and 10 nM (p < 0.05). In the cells exposed to smoke, lycopene increased 8-oxoguanine DNA glycosylase (OGG1) expression at 1 nM, 10 nM, 100 nM, and 1 μM (p < 0.05), but not at 10 μM. Lycopene at lower doses also improved Nei like DNA glycosylases (NEIL1, NEIL2, NEIL3), and connexin-43 (Cx43) protein levels (p < 0.05). Interestingly, lycopene at lower concentrations promoted OGG1 expression within the cells exposed to smoke to an even greater extent than the cells not exposed to smoke (p < 0.01). This may be attributed to the increased SR-B1 mRNA levels with cigarette smoke exposure (p < 0.05). Conclusions: Lycopene treatment at a lower dosage could inhibit smoke-induced oxidative stress and promote genome stability. These novel findings will shed light on the molecular mechanism of lycopene action against lung cancer.

scholarly journals The role of divalent cations in the regulation of microtubule assembly. In vivo studies on microtubules of the heliozoan axopodium using the ionophore A23187.

1976 ◽  
Vol 70 (3) ◽  
pp. 527-540 ◽  
Author(s):  
M Schliwa
Keyword(s):  
Divalent Cations ◽  
Light And Electron Microscopy ◽  
Microtubule Assembly ◽  
In Vivo Studies ◽  
Ionophore A23187 ◽  
Low Concentrations ◽  
Microtubule Formation

Low concentrations of calcium and magnesium ions have been shown to influence microtubule assembly in vitro. To test whether these cations also have an effect on microtubules in vivo, specimens of Actinosphaerium eichhorni were exposed to different concentrations of Ca++ and Mg++ and the divalent cation ionophore A23187. Experimental degradation and reformation of axopodia were studied by light and electron microscopy. In the presence of Ca++ and the ionophore axopodia gradually shorten, the rate of shortening depending on the concentrations of Ca++ and the ionophore used. Retraction of axopodia was observed with a concentration of Ca++ as low as 0.01 mM. After transfer to a Ca++-free solution containing EGTA, axopodia re-extend; the initial length is reached after about 2 h. Likewise, reformation of axopodia of cold-treated organisms is observed only in solutions of EGTA or Mg++, whereas it is completely inhibited in a Ca++ solution. Electron microscope studies demonstrate degradation of the axonemal microtubular array in organisms treated with Ca++ and A23187. No alteration was observed in organisms treated with Mg++ or EGTA plus ionophore. The results suggest that, in the presence of the ionophore, formation of axonemal microtubules can be regulated by varying the Ca++ concentration in the medium. Since A23187 tends to equilibrate the concentrations of divalent cations between external medium and cell interior, it is likely that microtubule formation invivo is influenced by micromolar concentrations of Ca++. These concentrations are low enough to be of physiological significance for a role in the regulation of microtubule assembly in vivo.

scholarly journals Assessment of an in vitro whole cigarette smoke exposure system: The Borgwaldt RM20S 8-syringe smoking machine

2011 ◽  
Vol 5 (1) ◽  
Author(s):  
Jason Adamson ◽  
David Azzopardi ◽  
Graham Errington ◽  
Colin Dickens ◽  
John McAughey ◽  
...  
Keyword(s):  
Cigarette Smoke ◽  
Smoke Exposure ◽  
Cigarette Smoke Exposure ◽  
Exposure System

scholarly journals The impact of cigarette smoke exposure, and COPD or asthma status on ABC transporter gene expression in human airway epithelial cells

2018 ◽  
Author(s):  
Jennifer A. Aguiar ◽  
Andrea Tamminga ◽  
Briallen Lobb ◽  
Ryan D. Huff ◽  
Jenny Nguyen ◽  
...  
Keyword(s):  
Gene Expression ◽  
Epithelial Cells ◽  
Cigarette Smoke ◽  
Abc Transporters ◽  
Airway Epithelial Cells ◽  
Cigarette Smoke Exposure ◽  
Airway Epithelial ◽  
Respiratory Mucosa

AbstractRationaleThe respiratory mucosa coordinates responses to infections, allergens, and exposures to air pollution. A relatively unexplored aspect of the respiratory mucosa are the expression and function of ATP Binding Cassette (ABC) transporters. ABC transporters are conserved in prokaryotes and eukaryotes, with humans expressing 48 transporters divided into 7 classes (ABCA, ABCB, ABCC, ABCD, ABDE, ABCF, and ABCG). Throughout the human body, ABC transporters regulate cAMP levels, chloride secretion, lipid transport, and anti-oxidant responses. A deeper exploration of the expression patterns of ABC transporters in the respiratory mucosa is warranted to determine their relevance in lung health and disease.MethodsWe used a bioinformatic approach complemented with in vitro experimental methods for validation of candidate ABC transporters. We analyzed the expression profiles of all 48 human ABC transporters in the respiratory mucosa using bronchial epithelial cell gene expression datasets available in NCBI GEO from well-characterized patient populations of healthy subjects and individuals that smoke cigarettes, or have been diagnosed with COPD or asthma. The Calu-3 airway epithelial cell line was used to interrogate selected results using a cigarette smoke extract exposure model.ResultsUsing 9 distinct gene-expression datasets of primary human airway epithelial cells, we completed a focused analysis on 48 ABC transporters in samples from healthy subjects and individuals that smoke cigarettes, or have been diagnosed with COPD or asthma. In situ gene expression data demonstrate that ABC transporters are i) variably expressed in epithelial cells from different airway generations (top three expression levels - ABCA5, ABCA13, and ABCC5), ii) regulated by cigarette smoke exposure (ABCA13, ABCB6, ABCC1, and ABCC3), and iii) differentially expressed in individuals with COPD and asthma (ABCA13, ABCC1, ABCC2, ABCC9). An in vitro cell culture model of cigarette smoke exposure was able to recapitulate the in situ changes observed in cigarette smokers for ABCA13 and ABCC1.ConclusionsOur in situ human gene expression data analysis reveals that ABC transporters are expressed throughout the airway generations in airway epithelial cells and can be modulated by environmental exposures important in chronic respiratory disease (e.g. cigarette smoking) and in individuals with chronic lung diseases (e.g. COPD or asthma). Our work highlights select ABC transporter candidates of interest and a relevant in vitro model that will enable a deeper understanding of the contribution of ABC transporters in the respiratory mucosa in lung health and disease.

scholarly journals Impaired Brain Mitochondrial Bioenergetics in the Ts65Dn Mouse Model of Down Syndrome Is Restored by Neonatal Treatment with the Polyphenol 7,8-Dihydroxyflavone

Antioxidants ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 62
Author(s):  
Daniela Valenti ◽  
Fiorenza Stagni ◽  
Marco Emili ◽  
Sandra Guidi ◽  
Renata Bartesaghi ◽  
...  
Keyword(s):  
Down Syndrome ◽  
Mouse Model ◽  
Critical Role ◽  
Hippocampal Neurogenesis ◽  
In Vivo Studies ◽  
Mitochondrial Bioenergetics ◽  
Ts65dn Mouse ◽  
Atp Production

Down syndrome (DS), a major genetic cause of intellectual disability, is characterized by numerous neurodevelopmental defects. Previous in vitro studies highlighted a relationship between bioenergetic dysfunction and reduced neurogenesis in progenitor cells from the Ts65Dn mouse model of DS, suggesting a critical role of mitochondrial dysfunction in neurodevelopmental alterations in DS. Recent in vivo studies in Ts65Dn mice showed that neonatal supplementation (Days P3–P15) with the polyphenol 7,8-dihydroxyflavone (7,8-DHF) fully restored hippocampal neurogenesis. The current study was aimed to establish whether brain mitochondrial bioenergetic defects are already present in Ts65Dn pups and whether early treatment with 7,8-DHF positively impacts on mitochondrial function. In the brain and cerebellum of P3 and P15 Ts65Dn pups we found a strong impairment in the oxidative phosphorylation apparatus, resulting in a deficit in mitochondrial ATP production and ATP content. Administration of 7,8-DHF (dose: 5 mg/kg/day) during Days P3–P15 fully restored bioenergetic dysfunction in Ts65Dn mice, reduced the levels of oxygen radicals and reinstated the hippocampal levels of PGC-1α. No pharmacotherapy is available for DS. From current findings, 7,8-DHF emerges as a treatment with a good translational potential for improving mitochondrial bioenergetics and, thus, mitochondria-linked neurodevelopmental alterations in DS.

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