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Eshaghi Ghalibaf MH, Taghavi zadeh Yazdi ME, Mansourian M, Mohammadian Roshan N, Boskabady MH. Evaluation of the protective effect of Curcuma longa and PPARγ agonist, pioglitazone on paraquat-induced lung injury in rats. Immun Inflamm Dis 2024; 12:e70001. [PMID: 39172009 PMCID: PMC11340013 DOI: 10.1002/iid3.70001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2024] [Revised: 07/29/2024] [Accepted: 08/06/2024] [Indexed: 08/23/2024] Open
Abstract
BACKGROUND The inhalation of paraquat (PQ), one of the most widely used herbicides in the world, can result in lung injury. Curcuma longa (Cl) has long history in traditional and folk medicine for the treatment of a wide range of disorders including respiratory diseases. AIM The aim of the present work was to evaluate the preventive effect of Cl on inhaled PQ-induced lung injury in rats. METHODS Male Wistar rats were divided into 8 groups (n = 7), one group exposed to saline (control) and other groups exposed to PQ aerosol. Saline (PQ), Cl extract, (two doses), curcumin (Cu), pioglitazone (Pio), and the combination of Cl-L + Pio and dexamethasone (Dex) were administered during the exposure period to PQ. Total and differential white blood cell (WBC) counts, oxidant and antioxidant indicators in the bronchoalveolar lavage (BALF), interleukin (IL)-10, and tumor necrosis alpha (TNF-α) levels in the lung tissues, lung histologic lesions score, and air way responsiveness to methacholine were evaluated. RESULTS WBC counts (Total and differential), malondialdehyde level, tracheal responsiveness (TR), IL-10, TNF-α and histopathological changes of the lung were markedly elevated but total thiol content and the activities of catalase and superoxide dismutase were decreased in the BALF in the PQ group. Both doses of Cl, Cu, Pio, Cl-L + Pio, and Dex markedly improved all measured variables in comparison with the PQ group. CONCLUSION CI, Pio, and Cl-L + Pio improved PQ-induced lung inflammation and oxidative damage comparable with the effects of Dex.
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Affiliation(s)
- Mohammad Hossein Eshaghi Ghalibaf
- Applied Biomedical Research CenterMashhad University of Medical SciencesMashhadIran
- Department of Physiology, School of MedicineMashhad University of Medical SciencesMashhadIran
| | | | - Mona Mansourian
- Student Research Committee, Faculty of MedicineMashhad University of Medical SciencesMashhadIran
| | - Nema Mohammadian Roshan
- Department of Pathology, Faculty of MedicineMashhad University of Medical SciencesMashhadIran
| | - Mohammad Hossein Boskabady
- Applied Biomedical Research CenterMashhad University of Medical SciencesMashhadIran
- Department of Physiology, School of MedicineMashhad University of Medical SciencesMashhadIran
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Shuvalova M, Dmitrieva A, Belousov V, Nosov G. The role of reactive oxygen species in the regulation of the blood-brain barrier. Tissue Barriers 2024:2361202. [PMID: 38808582 DOI: 10.1080/21688370.2024.2361202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Accepted: 05/23/2024] [Indexed: 05/30/2024] Open
Abstract
The blood-brain barrier (BBB) regulates the exchange of metabolites and cells between the blood and brain, and maintains central nervous system homeostasis. Various factors affect BBB barrier functions, including reactive oxygen species (ROS). ROS can act as stressors, damaging biological molecules, but they also serve as secondary messengers in intracellular signaling cascades during redox signaling. The impact of ROS on the BBB has been observed in multiple sclerosis, stroke, trauma, and other neurological disorders, making blocking ROS generation a promising therapeutic strategy for BBB dysfunction. However, it is important to consider ROS generation during normal BBB functioning for signaling purposes. This review summarizes data on proteins expressed by BBB cells that can be targets of redox signaling or oxidative stress. It also provides examples of signaling molecules whose impact may cause ROS generation in the BBB, as well as discusses the most common diseases associated with BBB dysfunction and excessive ROS generation, open questions that arise in the study of this problem, and possible ways to overcome them.
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Affiliation(s)
- Margarita Shuvalova
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, Moscow, Russia
- Department of metabolism and redox biology, Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Anastasiia Dmitrieva
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, Moscow, Russia
| | - Vsevolod Belousov
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, Moscow, Russia
- Department of metabolism and redox biology, Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
- Federal Center of Brain Research and Neurotechnologies, Federal Medical Biological Agency, Moscow, Russia
- Life Improvement by Future Technologies (LIFT) Center, Skolkovo, Moscow, Russia
| | - Georgii Nosov
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, Moscow, Russia
- Federal Center of Brain Research and Neurotechnologies, Federal Medical Biological Agency, Moscow, Russia
- Life Improvement by Future Technologies (LIFT) Center, Skolkovo, Moscow, Russia
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Airway Smooth Muscle Regulated by Oxidative Stress in COPD. Antioxidants (Basel) 2023; 12:antiox12010142. [PMID: 36671004 PMCID: PMC9854973 DOI: 10.3390/antiox12010142] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2022] [Accepted: 12/29/2022] [Indexed: 01/11/2023] Open
Abstract
Since COPD is a heterogeneous disease, a specific anti-inflammatory therapy for this disease has not been established yet. Oxidative stress is recognized as a major predisposing factor to COPD related inflammatory responses, resulting in pathological features of small airway fibrosis and emphysema. However, little is known about effects of oxidative stress on airway smooth muscle. Cigarette smoke increases intracellular Ca2+ concentration and enhances response to muscarinic agonists in human airway smooth muscle. Cigarette smoke also enhances proliferation of these cells with altered mitochondrial protein. Hydrogen peroxide and 8-isoprostans are increased in the exhaled breath condensate in COPD. These endogenous oxidants cause contraction of tracheal smooth muscle with Ca2+ dynamics through Ca2+ channels and with Ca2+ sensitization through Rho-kinase. TNF-α and growth factors potentiate proliferation of these cells by synthesis of ROS. Oxidative stress can alter the function of airway smooth muscle through Ca2+ signaling. These phenotype changes are associated with manifestations (dyspnea, wheezing) and pathophysiology (airflow limitation, airway remodeling, airway hyperresponsiveness). Therefore, airway smooth muscle is a therapeutic target against COPD; oxidative stress should be included in treatable traits for COPD to advance precision medicine. Research into Ca2+ signaling related to ROS may contribute to the development of a novel agent for COPD.
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Role of Airway Smooth Muscle in Inflammation Related to Asthma and COPD. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1303:139-172. [PMID: 33788192 DOI: 10.1007/978-3-030-63046-1_9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Airway smooth muscle contributes to both contractility and inflammation in the pathophysiology of asthma and COPD. Airway smooth muscle cells can change the degree of a variety of functions, including contraction, proliferation, migration, and the secretion of inflammatory mediators (phenotype plasticity). Airflow limitation, airway hyperresponsiveness, β2-adrenergic desensitization, and airway remodeling, which are fundamental characteristic features of these diseases, are caused by phenotype changes in airway smooth muscle cells. Alterations between contractile and hyper-contractile, synthetic/proliferative phenotypes result from Ca2+ dynamics and Ca2+ sensitization. Modulation of Ca2+ dynamics through the large-conductance Ca2+-activated K+ channel/L-type voltage-dependent Ca2+ channel linkage and of Ca2+ sensitization through the RhoA/Rho-kinase pathway contributes not only to alterations in the contractile phenotype involved in airflow limitation, airway hyperresponsiveness, and β2-adrenergic desensitization but also to alteration of the synthetic/proliferative phenotype involved in airway remodeling. These Ca2+ signal pathways are also associated with synergistic effects due to allosteric modulation between β2-adrenergic agonists and muscarinic antagonists. Therefore, airway smooth muscle may be a target tissue in the therapy for these diseases. Moreover, the phenotype changing in airway smooth muscle cells with focuses on Ca2+ signaling may provide novel strategies for research and development of effective remedies against both bronchoconstriction and inflammation.
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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.
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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.
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Kume H, Nishiyama O, Isoya T, Higashimoto Y, Tohda Y, Noda Y. Involvement of Allosteric Effect and K Ca Channels in Crosstalk between β₂-Adrenergic and Muscarinic M₂ Receptors in Airway Smooth Muscle. Int J Mol Sci 2018; 19:ijms19071999. [PMID: 29987243 PMCID: PMC6073859 DOI: 10.3390/ijms19071999] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 06/24/2018] [Accepted: 07/04/2018] [Indexed: 12/17/2022] Open
Abstract
To advance the development of bronchodilators for asthma and chronic obstructive pulmonary disease (COPD), this study was designed to investigate the mechanism of functional antagonism between β2-adrenergic and muscarinic M2 receptors, focusing on allosteric effects and G proteins/ion channels coupling. Muscarinic receptor antagonists (tiotropium, glycopyrronium, atropine) synergistically enhanced the relaxant effects of β2-adrenergic receptor agonists (procaterol, salbutamol, formoterol) in guinea pig trachealis. This crosstalk was inhibited by iberitoxin, a large-conductance Ca2+-activated K+ (KCa) channel inhibitor, whereas it was increased by verapamil, a L-type voltage-dependent Ca2+ (VDC) channel inhibitor; additionally, it was enhanced after tissues were incubated with pertussis or cholera toxin. This synergism converges in the G proteins (Gi, Gs)/KCa channel/VDC channel linkages. Muscarinic receptor antagonists competitively suppressed, whereas, β2-adrenergic receptor agonists noncompetitively suppressed muscarinic contraction. In concentration-inhibition curves for β2-adrenergic receptor agonists with muscarinic receptor antagonists, EC50 was markedly decreased, and maximal inhibition was markedly increased. Hence, muscarinic receptor antagonists do not bind to allosteric sites on muscarinic receptors. β2-Adrenergic receptor agonists bind to allosteric sites on these receptors; their intrinsic efficacy is attenuated by allosteric modulation (partial agonism). Muscarinic receptor antagonists enhance affinity and efficacy of β2-adrenergic action via allosteric sites in β2-adrenergic receptors (synergism). In conclusion, KCa channels and allosterism may be novel targets of bronchodilator therapy for diseases such as asthma and COPD.
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Affiliation(s)
- Hiroaki Kume
- Department of Respiratory Medicine and Allergology, Faculty of Medicine, Kindai University, 377-2 Ohnohigashi, Osakasayama 589-8511, Japan.
| | - Osamu Nishiyama
- Department of Respiratory Medicine and Allergology, Faculty of Medicine, Kindai University, 377-2 Ohnohigashi, Osakasayama 589-8511, Japan.
| | - Takaaki Isoya
- Department of Respiratory Medicine and Allergology, Faculty of Medicine, Kindai University, 377-2 Ohnohigashi, Osakasayama 589-8511, Japan.
| | - Yuji Higashimoto
- Department of Respiratory Medicine and Allergology, Faculty of Medicine, Kindai University, 377-2 Ohnohigashi, Osakasayama 589-8511, Japan.
| | - Yuji Tohda
- Department of Respiratory Medicine and Allergology, Faculty of Medicine, Kindai University, 377-2 Ohnohigashi, Osakasayama 589-8511, Japan.
| | - Yukihiro Noda
- Division of Clinical Sciences and Neuropsychopharmacology, Graduate School of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan.
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Regulation of Spontaneous Contractions in Intact Rat Bladder Strips and the Effects of Hydrogen Peroxide. BIOMED RESEARCH INTERNATIONAL 2018; 2018:2925985. [PMID: 29511675 PMCID: PMC5817331 DOI: 10.1155/2018/2925985] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 12/01/2017] [Accepted: 12/31/2017] [Indexed: 01/07/2023]
Abstract
Enhanced spontaneous contractions are associated with overactive bladder. Elevated levels of reactive oxygen species might contribute to enhanced spontaneous contractions. We investigated the regulation of spontaneous contractions and the effects of hydrogen peroxide (H2O2) in intact rat bladder strips. The spontaneous contractions were measured using a tissue bath system. The vehicle or the specific activators/blockers were applied and followed by the application of 0.003 g% H2O2. The basal tension, amplitude, and frequency of spontaneous contractions were quantified. Nisoldipine and bisindolylmaleimide 1 had no effects on spontaneous contractions. SKF96365 and Y27632 decreased basal tension and amplitude. Ryanodine slightly increased frequency. Both iberiotoxin and NS-1619 increased amplitude. Apamin reduced frequency but increased amplitude. NS-309 inhibited both the amplitude and frequency. The basal tension and amplitude increased when H2O2 was applied. Pretreatment with NS-309 inhibited H2O2-elicited augmented amplitude and frequency, while pretreatment with Y-27632 inhibited the augmented basal tension. The combined application of NS-309 and Y27632 almost eliminated spontaneous contractions and its augmentation induced by H2O2. In conclusion, Ca2+ influx, Rho kinase activation, and SK channel inactivation play important roles in spontaneous contractions in intact bladder strips, whereas only latter two mechanisms may be involved in H2O2-elicited increased spontaneous contractions.
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8
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Jernigan NL, Resta TC, Gonzalez Bosc LV. Altered Redox Balance in the Development of Chronic Hypoxia-induced Pulmonary Hypertension. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 967:83-103. [PMID: 29047083 DOI: 10.1007/978-3-319-63245-2_7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Normally, the pulmonary circulation is maintained in a low-pressure, low-resistance state with little resting tone. Pulmonary arteries are thin-walled and rely heavily on pulmonary arterial distension and recruitment for reducing pulmonary vascular resistance when cardiac output is elevated. Under pathophysiological conditions, however, active vasoconstriction and vascular remodeling lead to enhanced pulmonary vascular resistance and subsequent pulmonary hypertension (PH). Chronic hypoxia is a critical pathological factor associated with the development of PH resulting from airway obstruction (COPD, sleep apnea), diffusion impairment (interstitial lung disease), developmental lung abnormalities, or high altitude exposure (World Health Organization [WHO]; Group III). The rise in pulmonary vascular resistance increases right heart afterload causing right ventricular hypertrophy that can ultimately lead to right heart failure in patients with chronic lung disease. PH is typically characterized by diminished paracrine release of vasodilators, antimitogenic factors, and antithrombotic factors (e.g., nitric oxide and protacyclin) and enhanced production of vasoconstrictors and mitogenic factors (e.g., reactive oxygen species and endothelin-1) from the endothelium and lung parenchyma. In addition, phenotypic changes to pulmonary arterial smooth muscle cells (PASMC), including alterations in Ca2+ homeostasis, Ca2+ sensitivity, and activation of transcription factors are thought to play prominent roles in the development of both vasoconstrictor and arterial remodeling components of hypoxia-associated PH. These changes in PASMC function are briefly reviewed in Sect. 1 and the influence of altered reactive oxygen species homeostasis on PASMC function discussed in Sects. 2-4.
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Affiliation(s)
- Nikki L Jernigan
- Department Cell Biology and Physiology, Vascular Physiology Group, University of New Mexico Health Sciences Center, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Thomas C Resta
- Department Cell Biology and Physiology, Vascular Physiology Group, University of New Mexico Health Sciences Center, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Laura V Gonzalez Bosc
- Department Cell Biology and Physiology, Vascular Physiology Group, University of New Mexico Health Sciences Center, University of New Mexico, Albuquerque, NM, 87131, USA.
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Involvement of Ca 2+ Signaling in the Synergistic Effects between Muscarinic Receptor Antagonists and β₂-Adrenoceptor Agonists in Airway Smooth Muscle. Int J Mol Sci 2016; 17:ijms17091590. [PMID: 27657061 PMCID: PMC5037855 DOI: 10.3390/ijms17091590] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 09/02/2016] [Accepted: 09/08/2016] [Indexed: 12/25/2022] Open
Abstract
Long-acting muscarinic antagonists (LAMAs) and short-acting β2-adrenoceptor agonists (SABAs) play important roles in remedy for COPD. To propel a translational research for development of bronchodilator therapy, synergistic effects between SABAs with LAMAs were examined focused on Ca2+ signaling using simultaneous records of isometric tension and F340/F380 in fura-2-loaded tracheal smooth muscle. Glycopyrronium (3 nM), a LAMA, modestly reduced methacholine (1 μM)-induced contraction. When procaterol, salbutamol and SABAs were applied in the presence of glycopyrronium, relaxant effects of these SABAs are markedly enhanced, and percent inhibition of tension was much greater than the sum of those for each agent and those expected from the BI theory. In contrast, percent inhibition of F340/F380 was not greater than those values. Bisindolylmaleimide, an inhibitor of protein kinase C (PKC), significantly increased the relaxant effect of LAMA without reducing F340/F380. Iberiotoxin, an inhibitor of large-conductance Ca2+-activated K+ (KCa) channels, significantly suppressed the effects of these combined agents with reducing F340/F380. In conclusion, combination of SABAs with LAMAs synergistically enhances inhibition of muscarinic contraction via decreasing both Ca2+ sensitization mediated by PKC and Ca2+ dynamics mediated by KCa channels. PKC and KCa channels may be molecular targets for cross talk between β2-adrenoceptors and muscarinic receptors.
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Kume H, Fukunaga K, Oguma T. Research and development of bronchodilators for asthma and COPD with a focus on G protein/KCa channel linkage and β2-adrenergic intrinsic efficacy. Pharmacol Ther 2015; 156:75-89. [PMID: 26432616 DOI: 10.1016/j.pharmthera.2015.09.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Bronchodilators are used to improve symptoms and lung function in asthma and COPD. Airway smooth muscle tone is regulated by both muscarinic and β2-adrenergic receptor activity. Large-conductance Ca(2+)-activated K(+) (KCa) channels are activated by β2-adrenergic receptor agonists, via Gs, and suppressed by muscarinic receptor antagonists via Gi. This functional antagonism converges on the G protein/KCa channel linkages. Membrane potential regulated by KCa channels contributes to airway smooth muscle tension via Ca(2+) influx passing through voltage-dependent Ca(2+) (VDC) channels. The Gs/KCa/VDC channel linkage is a key process in not only physiological effects, but also in dysfunction of β2-adrenergic receptors and airway remodeling. Moreover, this pathway is involved in the synergistic effects between β2-adrenergic receptor agonists and muscarinic receptor antagonists. Intrinsic efficacy is also an important characteristic for both maintenance and loss of β2-adrenergic action. Allosteric modulators of G protein-coupled receptors contribute not only to this synergistic effect between β2-adrenergic and muscarinic M2 receptors, but also to intrinsic efficacy. The effects of weak partial agonists are suppressed by lowering receptor number, disordering receptor function, and enhancing functional antagonism; in contrast, those of full or strong partial agonists are not suppressed. Excessive exposure to full agonists causes β2-adrenergic desensitization; in contrast, exposure to partial agonists does not cause desensitization. Intrinsic efficacy may provide the rationale for the clinical use of β2-adrenergic receptor agonists in asthma and COPD. In conclusion, the G protein/KCa linkage and intrinsic efficacy (allosteric effects) may be therapeutic targets for research and development of novel agents against both airway obstruction and airway remodeling.
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Affiliation(s)
- Hiroaki Kume
- Department of Respiratory Medicine and Allergology, Kinki University Faculty of Medicine, Japan.
| | - Kentaro Fukunaga
- Division of Respiratory Medicine, Department of Internal Medicine, Shiga University of Medical Science, Japan
| | - Tetsuya Oguma
- Division of Respiratory Medicine, Department of Internal Medicine, Shiga University of Medical Science, Japan
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Abstract
Redox agents have been historically considered pathological agents which can react with and damage many biological macromolecules including DNA, proteins, and lipids. However, a growing number of reports have suggested that mammalian cells can rapidly respond to ligand stimulation with a change in intracellular ROS thus indicating that the production of intracellular redox agents is tightly regulated and that they serve as intracellular signaling molecules being involved in a variety of cell signaling pathways. Numerous observations have suggested that some members of the Ras GTPase superfamily appear to regulate the production of redox agents and that oxidants can function as effector molecules for the small GTPases, thus contributing to their overall biological function. In addition, many of the Ras superfamily small GTPases have been shown to be redox sensitive, thanks to the presence of redox-sensitive sequences in their primary structure. The action of redox agents on these redox-sensitive GTPases is similar to that of guanine nucleotide exchange factors in that they perturb GTPase nucleotide-binding interactions that result in the enhancement of the guanine nucleotide exchange of small GTPases. Thus, Ras GTPases may act both as upstream regulators and downstream effectors of redox agents. Here we overview current understanding concerning the interplay between Ras GTPases and redox agents, also taking into account pathological implications of misregulation of this cross talk and highlighting the potentiality of these cellular pathways as new therapeutical targets for different pathologies.
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Hydrogen peroxide increases nerve-evoked contractions in mouse tail artery by an endothelium-dependent mechanism. Eur J Pharmacol 2013; 698:362-9. [DOI: 10.1016/j.ejphar.2012.11.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Revised: 10/17/2012] [Accepted: 11/01/2012] [Indexed: 01/26/2023]
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13
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Effects of exercise and antioxidant supplementation on endothelial gene expression. Int J Cardiol 2012; 158:59-65. [DOI: 10.1016/j.ijcard.2010.12.104] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2010] [Revised: 11/04/2010] [Accepted: 12/30/2010] [Indexed: 11/20/2022]
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Sashio T, Kume H, Takeda N, Asano T, Tsuji S, Kondo M, Hasegawa Y, Shimokata K. Possible Involvement of Sphingosine-1-Phosphate/G(i)/RhoA pathways in adherence of eosinophils to pulmonary endothelium. Allergol Int 2012; 61:283-93. [PMID: 22361510 DOI: 10.2332/allergolint.10-oa-0299] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Accepted: 11/06/2011] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND Sphingosine-1-phosphate (S1P), a lysophospholipid released from inflammatory cells, causes cell migration by increasing cytokines and chemokines. This study was designed to determine whether S1P causes adherence of eosinophils to pulmonary endothelial cells via enhancement of adhesion molecule expression. METHODS Expression of VCAM-1 and ICAM-1 was assessed by RT-PCR and Western blot analysis in human pulmonary microvasucular endothelial cells (HPMVECs). The number of adherent eosinophils to HPMVECs was calculated according to adhesion assay. RESULTS Pre-treatment of HPMVECs with S1P increased mRNA and protein expression of VCAM-1, in contrast, did not dramatically increase those expression of ICAM-1. The maximal expression of these adhesion molecules in mRNA and protein was observed 4 and 8h after exposure to S1P, respectively. Pre-treatment with S1P also activated RhoA, a monomeric G protein; the ability of S1P to enhance the expression of VCAM-1 was attenuated by RhoA related inhibitors such as Y-27632, C3 exoenzyme, and GGTI-286. The effects of S1P on VCAM-1 were attenuated by pre-incubation with pertussis toxin, which catalyzes the ADP-ribosylation of G(i), a heterotrimeric G protein. After HPMVECs were treated with S1P, adhesion of human eosinophilic leukemic cell line (EoL-1) cells to HPMVECs was enhanced in a concentration-dependent manner. Augmented adherence of EoL-1 cells by S1P was also attenuated by Y-27632 and pertussis toxin. S1P causes adherence of eosinophils to pulmonary endothelium via RhoA activation. CONCLUSIONS S1P may act as a lipid mediator in asthma. The RhoA/Rho-kinase pathway may be a therapeutic target for preventing eosinophil infiltration to the airway.
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Affiliation(s)
- Toyokazu Sashio
- Department of Respiratory Medicine, Nagoya University Graduate School of Medicine, Aichi, Japan
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Lummus ZL, Wisnewski AV, Bernstein DI. Pathogenesis and disease mechanisms of occupational asthma. Immunol Allergy Clin North Am 2012; 31:699-716, vi. [PMID: 21978852 DOI: 10.1016/j.iac.2011.07.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Occupational asthma (OA) is one of the most common forms of work-related lung disease in all industrialized nations. The clinical management of patients with OA depends on an understanding of the multifactorial pathogenetic mechanisms that can contribute to this disease. This article discusses the various immunologic and nonimmunologic mechanisms and genetic susceptibility factors that drive the inflammatory processes of OA.
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Affiliation(s)
- Zana L Lummus
- Department of Internal Medicine, University of Cincinnati College of Medicine, 3255 Eden Avenue, Cincinnati, OH 45267-0563, USA
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The Interplay between ROS and Ras GTPases: Physiological and Pathological Implications. JOURNAL OF SIGNAL TRANSDUCTION 2011; 2012:365769. [PMID: 22175014 PMCID: PMC3235814 DOI: 10.1155/2012/365769] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Accepted: 10/18/2011] [Indexed: 01/23/2023]
Abstract
The members of the RasGTPase superfamily are involved in various signaling networks responsible for fundamental cellular processes. Their activity is determined by their guanine nucleotide-bound state. Recent evidence indicates that some of these proteins may be regulated by redox agents. Reactive oxygen species (ROSs) and reactive nitrogen species (RNSs) have been historically considered pathological agents which can react with and damage many biological macromolecules including DNA, proteins, and lipids. However, a growing number of reports have suggested that the intracellular production of ROS is tightly regulated and that these redox agents serve as signaling molecules being involved in a variety of cell signaling pathways. Numerous observations have suggested that some Ras GTPases appear to regulate ROS production and that oxidants function as effector molecules for the small GTPases, thus contributing to their overall biological function. Thus, redox agents may act both as upstream regulators and as downstream effectors of Ras GTPases. Here we discuss current understanding concerning mechanisms and physiopathological implications of the interplay between GTPases and redox agents.
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Zhou J, Alvarez-Elizondo MB, Botvinick E, George SC. Local small airway epithelial injury induces global smooth muscle contraction and airway constriction. J Appl Physiol (1985) 2011; 112:627-37. [PMID: 22114176 DOI: 10.1152/japplphysiol.00739.2011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Small airway epithelial cells form a continuous sheet lining the conducting airways, which serves many functions including a physical barrier to protect the underlying tissue. In asthma, injury to epithelial cells can occur during bronchoconstriction, which may exacerbate airway hyperreactivity. To investigate the role of epithelial cell rupture in airway constriction, laser ablation was used to precisely rupture individual airway epithelial cells of small airways (<300-μm diameter) in rat lung slices (∼250-μm thick). Laser ablation of single epithelial cells using a femtosecond laser reproducibly induced airway contraction to ∼70% of the original cross-sectional area within several seconds, and the contraction lasted for up to 40 s. The airway constriction could be mimicked by mechanical rupture of a single epithelial cell using a sharp glass micropipette but not with a blunt glass pipette. These results suggest that soluble mediators released from the wounded epithelial cell induce global airway contraction. To confirm this hypothesis, the lysate of primary human small airway epithelial cells stimulated a similar airway contraction. Laser ablation of single epithelial cells triggered a single instantaneous Ca(2+) wave in the epithelium, and multiple Ca(2+) waves in smooth muscle cells, which were delayed by several seconds. Removal of extracellular Ca(2+) or decreasing intracellular Ca(2+) both blocked laser-induced airway contraction. We conclude that local epithelial cell rupture induces rapid and global airway constriction through release of soluble mediators and subsequent Ca(2+)-dependent smooth muscle shortening.
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Affiliation(s)
- Jian Zhou
- Department of Biomedical Engineering, Universityof California, Irvine, CA 92697-2715, USA
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Abstract
Normal urinary bladder function is based on the proper contraction and relaxation of smooth muscle (SM), which constitutes the majority of the bladder wall. The contraction and relaxation of all SM involves a phosphorylation-dephosphorylation pathway involving the enzymes smooth muscle myosin light chain kinase (SMMLCK) and smooth muscle myosin light chain phosphatase (SMMLCP), respectively. Although originally thought to function just as a passive opposition to SMMLCK-driven SM contraction, it is now clear that SMMLCP activity is under an extremely complex molecular regulation via which SMMLCP inhibition can induce "calcium sensitization." This review provides a thorough summary of the literature regarding the molecular regulation of the SMMLCP with a focus on one of its major inhibitory pathways that is RhoA/Rho-kinase (ROK) including its activation pathways, effector molecules, and its roles in various pathological conditions associated with bladder dysfunction. Newly emerging roles of ROK outside of SM contractility are also discussed. It is concluded that the RhoA/ROK pathway is critical for the maintenance of basal SM tone of the urinary bladder and serves as a common final pathway of various contractile stimuli in rabbits, rats, mice, and pigs as well as humans. In addition, this pathway is upregulated in response to a number of pathological conditions associated with bladder SM dysfunction. Similarly, RhoA/Rho-kinase signaling is essential for normal ureteral function and development and is upregulated in response to ureteral outlet obstruction. In addition to its critical role in bladder SM function, a role of ROK in the urothelium is also beginning to emerge as well as roles for ROK in bladder infection and invasion and metastasis of bladder cancer.
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Nangle MR, Cotter MA, Cameron NE. Poly(ADP-Ribose) Polymerase Inhibition Reverses Nitrergic Neurovascular Dysfunctions in Penile Erectile Tissue from Streptozotocin-Diabetic Mice. J Sex Med 2010; 7:3396-403. [DOI: 10.1111/j.1743-6109.2010.01835.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Liu L, Duan JA, Tang YP, Ma HY, Su SL, Guo JM, Hua YQ. The protective effects of the active fraction of Shaofu Zhuyu decoction on hydrogen peroxide-induced oxidative injury in vascular smooth muscle cells. Molecules 2010; 15:5066-78. [PMID: 20714285 PMCID: PMC6257770 DOI: 10.3390/molecules15085066] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2010] [Revised: 07/15/2010] [Accepted: 07/19/2010] [Indexed: 02/07/2023] Open
Abstract
In this paper, the protective effects of the active fraction (SF-7) from Shaofu Zhuyu decoction (SFZYD) were tested on a hydrogen peroxide (H2O2)-induced rat vascular smooth muscle cells (VSMCs) oxidative injury model. This active fraction (SF-7) shows potent antioxidant properties. The cell viability and oxidative damage markers of VSMCs were determined after exposure to H2O2 for 16 hours. It was observed that SF-7 significantly increased cell survival and reduced apoptosis of H2O2-injured VSMCs. Moreover, SF-7 could markedly increase intracellular superoxide dismutase (SOD) activity and decrease the malondialdehyde (MDA) level in H2O2-injured VSMCs, and suppress the generation of intracellular reactive oxygen species (ROS), as well as intracellular Ca2+ concentration. Thus, SF-7 exhibits protective effects against H2O2-injury on VSMCs, which may be associated with its antioxidant properties. It is suggested that SF may be useful in the treatment of blood stasis syndrome in which oxidative injury is mainly implicated.
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Affiliation(s)
| | - Jin Ao Duan
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +86-25-85811916; Fax: +86-25-85811916
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Han JH, Lee MY, Lee SY, Chang IH, Kim HJ, Kim W, Myung SC. Effect of low concentrations of hydrogen peroxide on the contractile responses of rat detrusor smooth muscle strips. Eur J Pharmacol 2010; 638:115-20. [DOI: 10.1016/j.ejphar.2010.02.042] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2009] [Revised: 02/07/2010] [Accepted: 02/24/2010] [Indexed: 11/24/2022]
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Aghajanian A, Wittchen ES, Campbell SL, Burridge K. Direct activation of RhoA by reactive oxygen species requires a redox-sensitive motif. PLoS One 2009; 4:e8045. [PMID: 19956681 PMCID: PMC2778012 DOI: 10.1371/journal.pone.0008045] [Citation(s) in RCA: 161] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Accepted: 11/03/2009] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Rho family GTPases are critical regulators of the cytoskeleton and affect cell migration, cell-cell adhesion, and cell-matrix adhesion. As with all GTPases, their activity is determined by their guanine nucleotide-bound state. Understanding how Rho proteins are activated and inactivated has largely focused on regulatory proteins such as guanine nucleotide exchange factors (GEFs) and GTPase activating proteins (GAPs). However, recent in vitro studies have indicated that GTPases may also be directly regulated by redox agents. We hypothesized that this redox-based mechanism occurs in cells and affects cytoskeletal dynamics, and in this report we conclude this is indeed a novel mechanism of regulating the GTPase RhoA. METHODOLOGY/PRINCIPAL FINDINGS In this report, we show that RhoA can be directly activated by reactive oxygen species (ROS) in cells, and that this requires two critical cysteine residues located in a unique redox-sensitive motif within the phosphoryl binding loop. First, we show that ROS can reversibly activate RhoA and induce stress fiber formation, a well characterized readout of RhoA activity. To determine the role of cysteine residues in this mechanism of regulation, we generated cysteine to alanine RhoA mutants. Mutation of these cysteines abolishes ROS-mediated activation and stress fiber formation, indicating that these residues are critical for redox-regulation of RhoA. Importantly, these mutants maintain the ability to be activated by GEFs. CONCLUSIONS/SIGNIFICANCE Our findings identify a novel mechanism for the regulation of RhoA in cells by ROS, which is independent of classical regulatory proteins. This mechanism of regulation may be particularly relevant in pathological conditions where ROS are generated and the cellular redox-balance altered, such as in asthma and ischemia-reperfusion injury.
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Affiliation(s)
- Amir Aghajanian
- Department of Cell and Developmental Biology, University of North Carolina at Chapel Hill, Lineberger Comprehensive Cancer Center, Chapel Hill, North Carolina, United States of America.
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Shiraki A, Kume H, Oguma T, Makino Y, Ito S, Shimokata K, Honjo H, Kamiya K. Role of Ca2+ mobilization and Ca2+ sensitization in 8-iso-PGF 2 alpha-induced contraction in airway smooth muscle. Clin Exp Allergy 2008; 39:236-45. [PMID: 19134015 DOI: 10.1111/j.1365-2222.2008.03164.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
BACKGROUND Isoprostanes are prostaglandin (PG)-like compounds synthesized by oxidative stress, not by cyclooxygenase, and increase in bronchoalveolar lavage fluid of patients with asthma. The airway inflammation implicated in this disease may be amplified by oxidants. Although isoprostanes are useful biomarkers for oxidative stress, the action of these agents on airways has not been fully elucidated. OBJECTIVE This study was designed to determine the intracellular mechanisms underlying the effects of oxidative stress on airway smooth muscle, focused on Ca(2+) signalling pathways involved in the effect of 8-iso-PGF(2 alpha). METHODS Using simultaneous recording of isometric tension and F(340)/F(380) (an indicator of intracellular concentrations of Ca(2+), [Ca(2+)]i, we examined the correlation between tension and [Ca(2+)]i in response to 8-iso-PGF(2 alpha) in the fura-2 loaded tracheal smooth muscle. RESULTS Augmented tension and F(340)/F(380) by 8-iso-PGF(2 alpha) were attenuated by ICI-192605, an antagonist of thromboxane A(2) receptors (TP receptors). Moreover, D609, an antagonist of phosphatidylcholine-specific phospholipase C, markedly reduced both the tension and F(340)/F(380) induced by 8-iso-PGF(2 alpha), whereas U73122, an antagonist of phosphatidylinositol-specific phospholipase C, modestly inhibited them by 8-iso-PGF(2 alpha). SKF96365, a non-selective antagonist of Ca(2+) channels, markedly reduced both tension and F(340)/F(380) by 8-iso-PGF(2 alpha). However, diltiazem and verapamil, voltage-dependent Ca(2+) channel inhibitors, modestly attenuated tension although their reduction of F(340)/F(380) was not different from that by SKF96365. Y-27632, an inhibitor of Rho-kinase, significantly attenuated contraction induced by 8-iso-PGF(2 alpha) without reducing F(340)/F(380), whereas GF109203X and Go6983, protein kinase C inhibitors, did not markedly antagonize them although reducing F(340)/F(380) with a potency similar to Y-27632. CONCLUSION 8-iso-PGF(2 alpha) causes airway smooth muscle contraction via activation of TP receptors. Ca(2+) mobilization by SKF96365- and D609-sensitive Ca(2+) influx and Ca(2+) sensitization by Rho-kinase contribute to the intracellular mechanisms underlying the action of 8-iso-PGF(2 alpha). Rho-kinase may be a therapeutic target for the physiologic abnormalities induced by oxidative stress in airways.
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Affiliation(s)
- A Shiraki
- Department of Respiratory Medicine, Nagoya University Graduate School of Medicine, Nagoya University, Nagoya, Japan
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Pourmahram GE, Snetkov VA, Shaifta Y, Drndarski S, Knock GA, Aaronson PI, Ward JPT. Constriction of pulmonary artery by peroxide: role of Ca2+ release and PKC. Free Radic Biol Med 2008; 45:1468-76. [PMID: 18805479 DOI: 10.1016/j.freeradbiomed.2008.08.020] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2008] [Revised: 08/09/2008] [Accepted: 08/21/2008] [Indexed: 11/25/2022]
Abstract
Reactive oxygen species are implicated in pulmonary hypertension and hypoxic pulmonary vasoconstriction. We examined the effects of low concentrations of peroxide on intrapulmonary arteries (IPA). IPAs from Wistar rats were mounted on a myograph for recording tension and estimating intracellular Ca2+ using Fura-PE3. Ca2+ sensitization was examined in alpha-toxin-permeabilized IPAs, and phosphorylation of MYPT-1 and MLC(20) was assayed by Western blot. Peroxide (30 microM) induced a vasoconstriction with transient and sustained components and equivalent elevations of intracellular Ca2+. The transient constriction was strongly suppressed by indomethacin, the TP-receptor antagonist SQ-29584, and the Rho kinase inhibitor Y-27632, whereas sustained constriction was unaffected. Neither vasoconstriction nor elevation of intracellular Ca2+ was affected by removal of extracellular Ca2+, whereas dantrolene suppressed the former and ryanodine abolished the latter. Peroxide-induced constriction of permeabilized IPAs was unaffected by Y-27632 but abolished by PKC inhibitors; these also suppressed constriction in intact IPAs. Peroxide caused translocation of PKCalpha, but had no significant effect on MYPT-1 or MLC(20) phosphorylation. We conclude that in IPAs peroxide causes transient release of vasoconstrictor prostanoids, but sustained constriction is associated with release of Ca2+ from ryanodine-sensitive stores and a PKC-dependent but Rho kinase- and MLC(20)-independent constrictor mechanism.
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Abstract
PURPOSE OF REVIEW Plant pollens are one of the most common outdoor allergens. Pollen grains and subpollen particles can reach lower airways and induce symptoms of seasonal asthma and allergic rhinitis. Plants possess NAD(P)H oxidase activity that generates reactive oxygen species for physiological functions such as root-hair and pollen-tube growth, defense against microbial infections and cell signaling. The presence of NAD(P)H oxidases in pollens and their role in induction of airway inflammation have not been described until recently. RECENT FINDINGS We discovered the presence of NAD(P)H oxidase in ragweed and other plant pollens. These oxidases induce reactive oxygen species in mucosal cells (signal 1) independent of adaptive immunity. This reactive oxygen species facilitates antigen (signal 2)-induced allergic inflammation. Inhibiting signal 1 by administration of antioxidants attenuated ragweed extract-induced allergic inflammation. Likewise, abrogating signal 2 by antigen challenge in mice lacking T cells failed to induce allergic inflammation. SUMMARY Reactive oxygen species generated by pollen NAD(P)H oxidase play a major role in pathogenesis of allergic airway inflammation and airway hypersensitivity. Based on our findings, we propose a 'two signal hypothesis of allergic inflammation' in which both signal 1 (reactive oxygen species) and signal 2 (antigen presentation) are required in order to induce full-blown allergic inflammation.
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