1
|
Ansar M, Ivanciuc T, Garofalo RP, Casola A. Increased Lung Catalase Activity Confers Protection Against Experimental RSV Infection. Sci Rep 2020; 10:3653. [PMID: 32107411 PMCID: PMC7046725 DOI: 10.1038/s41598-020-60443-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 02/11/2020] [Indexed: 11/25/2022] Open
Abstract
Respiratory syncytial virus (RSV) infection in mouse and human lung is associated with oxidative injury and pathogenic inflammation. RSV impairs antioxidant responses by increasing the degradation of transcription factor NRF2, which controls the expression of several antioxidant enzyme (AOE) genes, including catalase. Since catalase is a key enzyme for the dismutation of virus-mediated generation of hydrogen peroxide (H2O2) we developed a model of intranasal supplementation of polyethylene glycol-conjugated catalase (PG-CAT) for RSV-infected mice. The results of our study show that PG-CAT supplementation was able to increase specific enzymatic activity along with reduction in H2O2 in the airways and had a significant protective effect against RSV-induced clinical disease and airway pathology. PG-CAT treated mice showed amelioration in airway obstruction, reduction in neutrophil elastase and inflammation. Improved airway hyperresponsiveness was also observed in mice that received PG-CAT as a treatment post-viral inoculation. In addition, PG-CAT greatly reduced the concentration of inflammatory cytokines and chemokines, including IL-1, TNF-α, IL-9, CXCL1, CCL2, and CCL5 in the bronchoalveolar lavage fluid of RSV-infected mice, without increasing viral replication in the lung. In conclusion, catalase supplementation may represent a novel pharmacologic approach to be explored in human for prevention or treatment of respiratory infections caused by RSV.
Collapse
Affiliation(s)
- Maria Ansar
- University of Texas Medical Branch, Department of Microbiology and Immunology Galveston, Galveston, TX, 77555, USA
| | - Teodora Ivanciuc
- University of Texas Medical Branch, Department of Pediatrics, Galveston, TX, 77555, USA
| | - Roberto P Garofalo
- University of Texas Medical Branch, Department of Microbiology and Immunology Galveston, Galveston, TX, 77555, USA
- University of Texas Medical Branch, Department of Pediatrics, Galveston, TX, 77555, USA
- University of Texas Medical Branch, Institute for Human Infections and Immunity, Galveston, TX, 77555, USA
| | - Antonella Casola
- University of Texas Medical Branch, Department of Microbiology and Immunology Galveston, Galveston, TX, 77555, USA.
- University of Texas Medical Branch, Department of Pediatrics, Galveston, TX, 77555, USA.
- University of Texas Medical Branch, Institute for Human Infections and Immunity, Galveston, TX, 77555, USA.
| |
Collapse
|
2
|
Jeong D, Kang C, Jung E, Yoo D, Wu D, Lee D. Porous antioxidant polymer microparticles as therapeutic systems for the airway inflammatory diseases. J Control Release 2016; 233:72-80. [PMID: 27151077 DOI: 10.1016/j.jconrel.2016.04.039] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 03/03/2016] [Accepted: 04/30/2016] [Indexed: 12/19/2022]
Abstract
Inhaling steroidal anti-inflammatory drugs is the most common treatment for airway inflammatory diseases such as asthma. However, frequent steroid administration causes adverse side effects. Therefore, the successful clinical translation of numerous steroidal drugs greatly needs pulmonary drug delivery systems which are formulated from biocompatible and non-immunogenic polymers. We have recently developed a new family of biodegradable polymer, vanillyl alcohol-containing copolyoxalate (PVAX) which is able to scavenge hydrogen peroxide and exert potent antioxidant and anti-inflammatory activity. In this work, we report the therapeutic potential of porous PVAX microparticles which encapsulate dexamethasone (DEX) as a therapeutic system for airway inflammatory diseases. PVAX microparticles themselves reduced oxidative stress and suppressed the expression of pro-inflammatory tumor necrosis factor-alpha and inducible nitric oxide synthase in the lung of ovalbumin-challenged asthmatic mice. However, DEX-loaded porous PVAX microparticles showed significantly enhanced therapeutic effects than PVAX microparticles, suggesting the synergistic effects of PVAX with DEX. In addition, PVAX microparticles showed no inflammatory responses to lung tissues. Given their excellent biocompatibility and intrinsic antioxidant and anti-inflammatory activity, PVAX microparticles hold tremendous potential as therapeutic systems for the treatment of airway inflammatory diseases such as asthma.
Collapse
Affiliation(s)
- Dahee Jeong
- Department of BIN Convergence Technology, Chonbuk National University, Baekje-daero 567, Jeonju, Chonbuk, 561-756, Republic of Korea
| | - Changsun Kang
- Department of BIN Convergence Technology, Chonbuk National University, Baekje-daero 567, Jeonju, Chonbuk, 561-756, Republic of Korea
| | - Eunkyeong Jung
- Department of BIN Convergence Technology, Chonbuk National University, Baekje-daero 567, Jeonju, Chonbuk, 561-756, Republic of Korea
| | - Donghyuck Yoo
- Department of BIN Convergence Technology, Chonbuk National University, Baekje-daero 567, Jeonju, Chonbuk, 561-756, Republic of Korea
| | - Dongmei Wu
- Department of BIN Convergence Technology, Chonbuk National University, Baekje-daero 567, Jeonju, Chonbuk, 561-756, Republic of Korea
| | - Dongwon Lee
- Department of BIN Convergence Technology, Chonbuk National University, Baekje-daero 567, Jeonju, Chonbuk, 561-756, Republic of Korea; Department of Polymer⋅Nano Science and Technology, Chonbuk National University, Baekje-daero 567, Jeonju, Chonbuk, 561-756, Republic of Korea.
| |
Collapse
|
3
|
Abstract
Pulmonary oxidant stress plays an important pathogenetic role in disease conditions including acute lung injury/adult respiratory distress syndrome (ALI/ARDS), hyperoxia, ischemia-reperfusion, sepsis, radiation injury, lung transplantation, COPD, and inflammation. Reactive oxygen species (ROS), released from activated macrophages and leukocytes or formed in the pulmonary epithelial and endothelial cells, damage the lungs and initiate cascades of pro-inflammatory reactions propagating pulmonary and systemic stress. Diverse molecules including small organic compounds (e.g. gluthatione, tocopherol (vitamin E), flavonoids) serve as natural antioxidants that reduce oxidized cellular components, decompose ROS and detoxify toxic oxidation products. Antioxidant enzymes can either facilitate these antioxidant reactions (e.g. peroxidases using glutathione as a reducing agent) or directly decompose ROS (e.g. superoxide dismutases [SOD] and catalase). Many antioxidant agents are being tested for treatment of pulmonary oxidant stress. The administration of small antioxidants via the oral, intratracheal and vascular routes for the treatment of short- and long-term oxidant stress showed rather modest protective effects in animal and human studies. Intratracheal and intravascular administration of antioxidant enzymes are being currently tested for the treatment of acute oxidant stress. For example, intratracheal administration of recombinant human SOD is protective in premature infants exposed to hyperoxia. However, animal and human studies show that more effective delivery of drugs to cells experiencing oxidant stress is needed to improve protection. Diverse delivery systems for antioxidants including liposomes, chemical modifications (e.g. attachment of masking pegylated [PEG]-groups) and coupling to affinity carriers (e.g. antibodies against cellular adhesion molecules) are being employed and currently tested, mostly in animal and, to a limited extent, in humans, for the treatment of oxidant stress. Further studies are needed, however, in order to develop and establish effective applications of pulmonary antioxidant interventions useful in clinical practice. Although beyond the scope of this review, antioxidant gene therapies may eventually provide a strategy for the management of subacute and chronic pulmonary oxidant stress.
Collapse
Affiliation(s)
- Melpo Christofidou-Solomidou
- Institute of Environmental Medicine and Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | | |
Collapse
|
4
|
Nemoto T, Kawakami S, Yamashita F, Hashida M. Efficient protection by cationized catalase against H2O2 injury in primary cultured alveolar epithelial cells. J Control Release 2007; 121:74-80. [PMID: 17610981 DOI: 10.1016/j.jconrel.2007.05.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2006] [Revised: 05/11/2007] [Accepted: 05/17/2007] [Indexed: 01/23/2023]
Abstract
Increasing evidence suggests that hydrogen peroxide plays an important role in alveolar epithelial injury produced during many inflammatory lung diseases. In this study, the successful prevention of hydrogen peroxide (H(2)O(2))-induced injury in primary cultured rabbit alveolar epithelial cells by cationized catalase is described. Cationized catalase was synthesized by direct chemical modification to enhance its association with alveolar epithelial cells. Cationized catalase exhibited a 22.3-fold higher cellular association at 2 h than native catalase, and incubation of cationized catalase with the cells produced a 2.19-fold intracellular catalase activity, which suggested that cationized catalase distributed both to the cell membrane and into the cell interior. Cationized catalase markedly suppressed H(2)O(2)-induced cell injury. In addition, electron spin resonance spectrometry analysis revealed that cationized catalase effectively eliminated H(2)O(2) produced in the medium by glucose plus glucose oxidase. On the other hand, polyethylene glycol-modified catalase (PEG-catalase) did not have any protective effect against H(2)O(2)-induced cell injury although PEG-catalase exhibited a 2.49-fold higher cellular association at 2 h than native catalase. These results suggest that cationization of catalase is a promising strategy for the treatment of many of inflammatory lung diseases.
Collapse
Affiliation(s)
- Takayuki Nemoto
- Department of Drug Delivery Research, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | | | | | | |
Collapse
|
5
|
Anseth JW, Goffin AJ, Fuller GG, Ghio AJ, Kao PN, Upadhyay D. Lung surfactant gelation induced by epithelial cells exposed to air pollution or oxidative stress. Am J Respir Cell Mol Biol 2005; 33:161-8. [PMID: 15860796 PMCID: PMC2715310 DOI: 10.1165/rcmb.2004-0365oc] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Lung surfactant lowers surface tension and adjusts interfacial rheology to facilitate breathing. A novel instrument, the interfacial stress rheometer (ISR), uses an oscillating magnetic needle to measure the shear viscosity and elasticity of a surfactant monolayer at the air-water interface. The ISR reveals that calf lung surfactant, Infasurf, exhibits remarkable fluidity, even when exposed to air pollution residual oil fly ash (ROFA), hydrogen peroxide (H2O2), or conditioned media from resting A549 alveolar epithelial cells (AEC). However, when Infasurf is exposed to a subphase of the soluble fraction of ROFA- or H2O2-treated AEC conditioned media, there is a prominent increase in surfactant elasticity and viscosity, representing two-dimensional gelation. Surfactant gelation is decreased when ROFA-AEC are pretreated with inhibitors of cellular reactive oxygen species (ROS), or with a mitochondrial anion channel inhibitor, as well as when A549-rho0 cells that lack mitochondrial DNA and functional electron transport are investigated. These results implicate both mitochondrial and nonmitochondrial ROS generation in ROFA-AEC-induced surfactant gelation. A549 cells treated with H2O2 demonstrate a dose-dependent increase in lung surfactant gelation. The ISR is a unique and sensitive instrument to characterize surfactant gelation induced by oxidatively stressed AEC.
Collapse
Affiliation(s)
- Jay W Anseth
- Department of Chemical Engineering, Stanford University Medical Center, 300 Pasteur Drive, Stanford, CA 94305-5236, USA
| | | | | | | | | | | |
Collapse
|
6
|
Connor N, Williams C, Ciesielski W, Zimmerman J. Global effects of xanthine oxidase stress on alveolar type II cells. Pediatr Crit Care Med 2002; 3:280-287. [PMID: 12780970 DOI: 10.1097/00130478-200207000-00016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE: To delineate biochemical details of graded xanthine oxidase stress toward cultured alveolar type II cells, particularly oxidant-mediated damage of type II cell nucleic acid, protein, and lipid, as an in vitro model of distant ischemia-reperfusion lung injury. DESIGN: In vitro injury model using native rat and immortalized mouse alveolar type II cells and exogenous xanthine oxidase. SETTING: Research laboratory. Measurement: Cultured type II cells were subjected to xanthine oxidase-derived reactive oxygen stress at variable concentrations and incubation times. Reduction of type II cell double-stranded DNA, inhibition of de novo phosphatidyl choline synthesis, enhancement of lipid peroxidation, and suppression of mitochondrial redox capacity were analyzed in relation to high-intensity (xanthine oxidase, 25 munits/mL) oxidant stress. Alterations in type II cell cellular glutathione-related antioxidant repertoire were assessed at both high-intensity and low-intensity (xanthine oxidase, 1 munits/mL) oxidant stress. MAIN RESULTS: High-intensity xanthine oxidase stress significantly increased type II cell DNA strand breakage, inhibited de novo phosphatidyl choline synthesis, diminished mitochondrial integrity, and enhanced lipid peroxidation in the absence of overt cytolysis. This injury was modulated with addition of exogenous glutathione peroxidase, or catalase/superoxide dismutase, but not glutathione or N-acetylcysteine. Although aspects of the glutathione antioxidant repertoire were similarly diminished with high-intensity xanthine oxidase stress, low-dose (long duration) xanthine oxidase stress augmented the activities of type II cell glutathione peroxidase and gamma-glutamyl transferase (the rate-limiting enzyme in glutathione synthesis). CONCLUSION: High-intensity xanthine oxidase stress (in vitro model of in vivo ischemia-reperfusion) may overwhelm type II cell antioxidant defenses and mediate oxidant injury to nucleic acid, protein, and lipid in the absence of cell lysis. Immortalized murine type II cells seem to appropriately model xanthine oxidase-mediated nucleic acid and protein injury of native rat type II cells. Exogenous glutathione peroxidase reduces oxidant injury in this in vitro model. Depending on magnitude (and possibly duration) of the xanthine oxidase stress, type II cell glutathione antioxidant elements may be diminished or enhanced.
Collapse
Affiliation(s)
- Neil Connor
- Department of Pediatrics, Division of Critical Care Medicine, University of Wisconsin Children's Hospital, Madison, WI (NC, CW, WC, JZ); and the Departments of Pediatrics and Anesthesia, Division of Critical Care Medicine, Children's Hospital and Regional Medical Center, Seattle, WA (WC, JZ)
| | | | | | | |
Collapse
|
7
|
Patel AB, Sokolowski J, Davidson BA, Knight PR, Holm BA. Halothane potentiation of hydrogen peroxide-induced inhibition of surfactant synthesis: the role of type II cell energy status. Anesth Analg 2002; 94:943-7, table of contents. [PMID: 11916801 DOI: 10.1097/00000539-200204000-00031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
UNLABELLED Small concentrations of inhaled anesthetics can affect Type II cell surfactant production and exacerbate oxidant-mediated lung injury. We hypothesized that inhaled anesthetics augment oxidant-induced Type II pneumocyte dysfunction related to their different effects on cellular adenosine triphosphate (ATP) status. Freshly isolated Type II cells were exposed to different concentrations of hydrogen peroxide (H2O2) in the presence or absence of an in vitro halothane exposure. Cells exposed to 100 microM H2O2 alone demonstrated a 23% decrease in ATP levels and a 32% decrease in phosphatidylcholine (PC) synthesis compared with controls. Halothane alone decreased PC synthesis by only 12% and reduced ATP levels by 20%. However, when exposed to both halothane and H2O2 together, ATP levels decreased by 40%, and PC synthesis rates decreased by 51%. Pretreatment of cells with nicotinamide, an inhibitor of poly adenosine diphosphate ribose polymerase, completely prevented the ATP loss and PC synthesis decline caused by H2O2 alone, but it had no effect on the halothane-augmented portion of the cell injury. These data suggest that the ability of halothane to enhance oxidative damage may be related to its own specific effects on cell energetics that may not be amenable to the same treatments used to mitigate other cellular mechanisms of oxidative stress. IMPLICATIONS A mediator of inflammation (hydrogen peroxide) and an inhaled anesthetic (halothane) interact to decrease cell energy and secretion of a substance (surfactant) required for healthy lung function from cells that line gas-exchange compartments. This interaction represents a possible mechanism by which inflammatory lung disease may become more severe intraoperatively.
Collapse
Affiliation(s)
- Alka B Patel
- Department of Pediatrics, State University of New York at Buffalo, School of Medicine and Biomedical Sciences, Buffalo, New York 14214, USA
| | | | | | | | | |
Collapse
|
8
|
Yang T, Li Y, Liu Q, Tao J, Wu W, Huang H. Isoflurane aggravates the decrease of phosphatidycholine synthesis in alveolar type II cells induced by hydrogen peroxide. DRUG METABOLISM AND DRUG INTERACTIONS 2002; 18:243-9. [PMID: 11791887 DOI: 10.1515/dmdi.2001.18.3-4.243] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The influence of isoflurane (Iso) on the synthesis and secretion of phosphatidylcholine (PC) of alveolar type II cells (AT II cells) injured by hydrogen peroxide (H2O2) was investigated. After primary culturing for 32 h, AT II cells isolated and purified from adult Sprague-Dawley rats were randomly divided into six groups: control group, 02.8 mM Iso group, 2.8 mM Iso group, 75 microM H2O2 group, 75 microM H2O2 + 0.28 mM Iso group, and 75 microM H202 + 2.8 mM Iso group. Synthesis and secretion of phosphatidylcholine (PC) were detected by 3H-choline chloride incorporation. It was found that 0.28 mM and 2.8 mM Iso significantly reduced PC synthesis compared with the control group (p <0.05, p <0.01, respectively), but not PC secretion. 75 microM H2O2 markedly decreased the synthesis and secretion of PC in AT II cells compared with the control group (p <0.01). 0.28 mM and 2.8 mM Iso aggravated the decrease of PC synthesis induced by H2O2 (p <0.05, p <0.01, respectively), but did not affect PC secretion. These findings suggest that Iso itself may inhibit the synthesis of PC of AT II cells in vitro and further damage the cells' function under peroxidation.
Collapse
Affiliation(s)
- T Yang
- Department ofAnesthesiology, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | | | | | | | | | | |
Collapse
|
9
|
Abstract
Protection of alveolar epithelial cells (alveolocytes) and vascular endothelial cells against pulmonary oxidative stress is an important problem. An inadequate delivery to the target cells limits the protective utility of the antioxidant enzymes, superoxide dismutase (SOD) and catalase. SOD and catalase modifications, such as coupling with polyethylene glycol and encapsulation in liposomes, prolong the life span of the active enzymes in vivo. The airway administration of SOD and catalase protects alveolocytes against hyperoxic oxidative stress. Although pulmonary endothelium is poorly accessible from the airways, it is accessible from circulation. However, antioxidant enzymes and their derivatives display poor targeting to pulmonary endothelium. To improve the targeting and provide intracellular delivery to endothelium, the enzymes can be conjugated with antibodies against endothelial antigens, such as angiotensin-converting enzyme and adhesion molecules [intercellular adhesion molecule-1 (ICAM-1) or platelet-endothelial cell adhesion molecule-1 (PECAM-1)]. These immunoconjugates accumulate in the pulmonary vasculature in intact animals, enter endothelium, and augment the antioxidant defenses. The immunoconjugates directed against ICAM-1 and PECAM-1 may also provide a secondary therapeutic benefit by blocking of sequestration and infiltration of leukocytes in the lungs. Further investigations are necessary to evaluate the therapeutic effectiveness of the vascular immunotargeting of antioxidant enzymes and solve technical problems associated with production of safe, clinically useful conjugates.
Collapse
Affiliation(s)
- V R Muzykantov
- Institute for Environmental Medicine and Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA.
| |
Collapse
|
10
|
Saugstad OD. Bronchopulmonary dysplasia and oxidative stress: are we closer to an understanding of the pathogenesis of BPD? Acta Paediatr 1997; 86:1277-82. [PMID: 9475300 DOI: 10.1111/j.1651-2227.1997.tb14897.x] [Citation(s) in RCA: 95] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In recent years a body of data has accumulated, linking the development of bronchopulmonary dysplasia (BPD) to increased oxidative stress in the first few days after birth, since high concentrations of metabolites reflecting increased peroxidation products such as pentane, ethane, protein carbonyl, o-tyrosine, allantoin and F2-isoprostanes, as well as low levels of glutathione and sulfhydryl/total protein ratio, also reflecting increased oxidative load, have been found in the premature infants at risk of or developing BPD. Oxidative stress seems to increase lung antioxidants in some experimental models of BPD and hyperoxia affects foetal lung growth. There are similarities between inflammation and hypoxia/reoxygenation, since both activate a number of inflammatory mediators such as cytokines and adhesion molecules, some of which are found in high concentrations in tracheal aspirate fluid of infants developing BPD. Surfactant production and function are also altered by both hyperoxia and reactive oxygen species per se, making the lungs more vulnerable to injury. This new knowledge may result in new and more efficient therapeutic approaches, hopefully leading to the eradication of BPD in the near future.
Collapse
Affiliation(s)
- O D Saugstad
- Department of Paediatric Research, The National Hospital, University of Oslo, Norway
| |
Collapse
|
11
|
Manuel SM, Guo Y, Matalon S. Exosurf enhances adenovirus-mediated gene transfer to alveolar type II cells. THE AMERICAN JOURNAL OF PHYSIOLOGY 1997; 273:L741-8. [PMID: 9357848 DOI: 10.1152/ajplung.1997.273.4.l741] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We assessed the role of surfactant replacement mixtures in the enhancement of adenovirus-mediated gene transfer to pulmonary epithelial cells both in vitro and in vivo. A549 cells, a pulmonary epithelium-derived adenocarcinoma cell line, were incubated with either media alone or media containing 10 microg phospholipid/ml Exosurf or Infasurf for 50 min followed by addition of a replication-deficient adenovirus (E1-deleted) expressing the luciferase reporter gene [AdCMV-Luc; 10 plaque-forming units (PFU)/cell] for 4 h. Pretreatment with Exosurf, but not Infasurf, at 37 degrees C, but not at 4 degrees C, enhanced luciferase activity in A549 cells 24 h later by 156% (P < 0.01). Intratracheal instillation of AdCMV-Luc (2 x 10(9) PFU) into rats resulted in luciferase expression mainly in alveolar macrophages and to a smaller extent in alveolar type II (ATII) cells 24 h later. However, when the AdCMV-Luc instillation was preceded by Exosurf (250 microl; 25 mg/ml), a 10-fold increase in ATII cell luciferase activity was noted. Preincubation of cultured ATII cells with Exosurf also enhanced their transfection by AdCMV-Luc by 515% (P < 0.001). The results of these studies provide a new strategy for targeting ATII cells for gene delivery.
Collapse
Affiliation(s)
- S M Manuel
- Department of Anesthesiology, University of Alabama at Birmingham, 35233-6810, USA
| | | | | |
Collapse
|
12
|
Pacht ER, Abernathy F. Prevention of intracellular adenosine triphosphate depletion after sublethal oxidant injury to rat type II alveolar epithelial cells with exogenous glutathione and N-acetylcysteine. Am J Med Sci 1995; 310:133-7. [PMID: 7573115 DOI: 10.1097/00000441-199510000-00001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The alveolar epithelial cells of the lower respiratory tract are exposed continuously to injurious agents, including oxygen radicals. The type II alveolar epithelial cell is critically important to the normal function of the lung, because it is responsible for synthesis of surfactant and other essential duties. In the current investigation, the authors documented the loss of intracellular adenosine triphosphate (ATP) after exposure of the cells to sublethal concentrations of hydrogen peroxide (H2O2) and hypochlorous acid. Subsequent experiments attempted to alleviate or prevent this oxidant mediated loss of ATP by preincubating the cells with either glutathione or N-acetylcysteine (NAC). Initially, it was determined that exposure of the type II cells to 250 microM hypochlorous acid or 250 microM H2O2 for 1 hour each would cause significant loss of type II cell ATP. However, preincubation with glutathione (1,000 microM) inhibited the loss of ATP after both exposure to 250 microM H2O2 (24 +/- 3% loss of ATP without glutathione compared with 13 +/- 2% loss with glutathione, P < 0.05), and 250 microM hypochlorous acid (12 +/- 2% loss of ATP without glutathione compared with 1 +/- 1% increase of ATP with glutathione). Similar results were obtained using NAC (2 mg/mL) after exposure to 250 microM H2O2 (23 +/- 2% loss of ATP without NAC compared with a 4 +/- 3% loss of ATP with NAC). This study demonstrates that exogenous glutathione and NAC are able to protect type II cells from oxidant mediated sublethal injury and loss of intracellular ATP stores.
Collapse
Affiliation(s)
- E R Pacht
- Department of Medicine, Ohio State University, Columbus, USA
| | | |
Collapse
|
13
|
BAKER MS. Free radicals and connective tissue damage. ACTA ACUST UNITED AC 1994. [DOI: 10.1016/s0167-7306(08)60448-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
|
14
|
Bauer ML, Beckman JS, Bridges RJ, Fuller CM, Matalon S. Peroxynitrite inhibits sodium uptake in rat colonic membrane vesicles. BIOCHIMICA ET BIOPHYSICA ACTA 1992; 1104:87-94. [PMID: 1550856 DOI: 10.1016/0005-2736(92)90135-9] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Peroxynitrite (ONOO-) is a potent oxidizing agent that initiates lipid peroxidation and sulfhydryl oxidation and may be responsible for a portion of the cytotoxicity attributed to superoxide anion (.O2-). We quantified the extent to which ONOO-, xanthine plus xanthine oxidase (XO) and hydrogen peroxide (H2O2), decreased sodium (Na+) uptake into membrane vesicles derived from colonic cells of dexamethasone-treated rats. Carrier-free 22Na+ uptake into vesicles was measured in the presence of an inside-negative membrane potential, produced by the addition of the potassium ionophore valinomycin (10 microM) after removal of all external potassium by cation exchange chromatography. Preincubation of vesicles with either 100 microM or 1 mM ONOO- for 30 s decreased the amiloride-blockable fraction of Na+ uptake by 27 +/- 7% and 65 +/- 2%, respectively (means +/- S.E.; n greater than or equal to 5; P less than 0.05 from control). However, the amiloride-insensitive part of Na+ uptake was not affected, indicating that there was no overt destruction of these vesicles by these ONOO- concentrations. Decomposed ONOO-, hydrogen peroxide (1 microM-10 mM), or xanthine (500 microM) plus XO (10-30 mU/ml), either in the absence or in the presence of 100 microM FeEDTA, did not decrease Na+ uptake. These data suggest that ONOO- is a potent injurious agent that can compromise Na+ uptake across epithelial cells, possibly by damaging Na+ channels.
Collapse
Affiliation(s)
- M L Bauer
- Department of Pediatrics, University of Alabama, Birmingham 35223
| | | | | | | | | |
Collapse
|