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Sriram K, Insel MB, Insel PA. Inhaled β2 Adrenergic Agonists and Other cAMP-Elevating Agents: Therapeutics for Alveolar Injury and Acute Respiratory Disease Syndrome? Pharmacol Rev 2021; 73:488-526. [PMID: 34795026 DOI: 10.1124/pharmrev.121.000356] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 08/15/2021] [Indexed: 12/15/2022] Open
Abstract
Inhaled long-acting β-adrenergic agonists (LABAs) and short-acting β-adrenergic agonists are approved for the treatment of obstructive lung disease via actions mediated by β2 adrenergic receptors (β2-ARs) that increase cellular cAMP synthesis. This review discusses the potential of β2-AR agonists, in particular LABAs, for the treatment of acute respiratory distress syndrome (ARDS). We emphasize ARDS induced by pneumonia and focus on the pathobiology of ARDS and actions of LABAs and cAMP on pulmonary and immune cell types. β2-AR agonists/cAMP have beneficial actions that include protection of epithelial and endothelial cells from injury, restoration of alveolar fluid clearance, and reduction of fibrotic remodeling. β2-AR agonists/cAMP also exert anti-inflammatory effects on the immune system by actions on several types of immune cells. Early administration is likely critical for optimizing efficacy of LABAs or other cAMP-elevating agents, such as agonists of other Gs-coupled G protein-coupled receptors or cyclic nucleotide phosphodiesterase inhibitors. Clinical studies that target lung injury early, prior to development of ARDS, are thus needed to further assess the use of inhaled LABAs, perhaps combined with inhaled corticosteroids and/or long-acting muscarinic cholinergic antagonists. Such agents may provide a multipronged, repurposing, and efficacious therapeutic approach while minimizing systemic toxicity. SIGNIFICANCE STATEMENT: Acute respiratory distress syndrome (ARDS) after pulmonary alveolar injury (e.g., certain viral infections) is associated with ∼40% mortality and in need of new therapeutic approaches. This review summarizes the pathobiology of ARDS, focusing on contributions of pulmonary and immune cell types and potentially beneficial actions of β2 adrenergic receptors and cAMP. Early administration of inhaled β2 adrenergic agonists and perhaps other cAMP-elevating agents after alveolar injury may be a prophylactic approach to prevent development of ARDS.
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Affiliation(s)
- Krishna Sriram
- Departments of Pharmacology (K.S., P.A.I.) and Medicine (P.A.I.), University of California San Diego, La Jolla, California; Department of Medicine (M.B.I.) University of Arizona, Tucson, Arizona
| | - Michael B Insel
- Departments of Pharmacology (K.S., P.A.I.) and Medicine (P.A.I.), University of California San Diego, La Jolla, California; Department of Medicine (M.B.I.) University of Arizona, Tucson, Arizona
| | - Paul A Insel
- Departments of Pharmacology (K.S., P.A.I.) and Medicine (P.A.I.), University of California San Diego, La Jolla, California; Department of Medicine (M.B.I.) University of Arizona, Tucson, Arizona
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Ischemia-Reperfusion Injury in Lung Transplantation. Cells 2021; 10:cells10061333. [PMID: 34071255 PMCID: PMC8228304 DOI: 10.3390/cells10061333] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 05/24/2021] [Accepted: 05/26/2021] [Indexed: 02/08/2023] Open
Abstract
Lung transplantation has been established worldwide as the last treatment for end-stage respiratory failure. However, ischemia–reperfusion injury (IRI) inevitably occurs after lung transplantation. The most severe form of IRI leads to primary graft failure, which is an important cause of morbidity and mortality after lung transplantation. IRI may also induce rejection, which is the main cause of mortality in recipients. Despite advances in donor management and graft preservation, most donor grafts are still unsuitable for transplantation. Although the pulmonary endothelium is the primary target site of IRI, the pathophysiology of lung IRI remains incompletely understood. It is essential to understand the mechanism of pulmonary IRI to improve the outcomes of lung transplantation. Therefore, we reviewed the state-of-the-art in the management of pulmonary IRI after lung transplantation. Recently, the ex vivo lung perfusion (EVLP) system has been clinically introduced worldwide. Various promising therapeutic strategies for the protection of the endothelium against IRI, including EVLP, inhalation therapy with therapeutic gases and substances, fibrinolytic treatment, and mesenchymal stromal cell therapy, are awaiting clinical application. We herein review the latest advances in the field of pulmonary IRI in lung transplantation.
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Demey L, Van Muylem A, Malinovschi A, Haccuria A, Perez-Bogerd S, Michils A. Exploring the sites and kinetics of bronchodilator response to β-2 agonists in asthma. J Appl Physiol (1985) 2021; 130:1106-1113. [PMID: 33444118 DOI: 10.1152/japplphysiol.00643.2020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We previously documented, in patients with asthma, three different profiles of bronchodilation induced by short-acting β-2 mimetics (SABA), characterized by dilation up to central, preacinar, and intra-acinar airways assessed by ventilation distribution tests and associated with no change, increase, and decrease of fractional exhaled nitric oxide concentration (FENO), respectively. To investigate the dynamics of these profiles over the entire SABA action period, assuming that bronchodilation of proximal and peripheral airways could exhibit varying kinetics due to differences in the distribution of β-2 receptors in both the central and peripheral human airways. FENO, forced expired volume in one second (FEV1), and the slope (S) of He and SF6 phase III (single-breath test) were measured in asthma patients before, and up to 6 h after SABA inhalation (salbutamol 400 µg). SHe and SSF6 decrease reflects pre- and intra-acinar obstruction relief, respectively. Thirty patients with asthma (12F/18M, aged 45 ± 18 yr) were divided into groups with positive (NO+, n = 9), negative (NO-, n = 11), and no (NO=, n = 10) FENO acute change. In the NO- group, FEV1 increased for up to 4 h, whereas FENO, SHe, and SF6 decreased in the early phase only. In stark contrast, in the NO+ group, FEV1 increased in the early phase only whereas the FENO increase and the SHe decrease lasted for up to 4 h. This study documents various profiles of SABA-induced bronchodilation in patients with asthma, differing both by sites and dynamics of the bronchodilator process. So, detailed understanding of the bronchodilator effect of β2-agonists in asthma should not solely be limited to studying their impact on FEV1.NEW & NOTEWORTHY FEV1 increase usually observed after the inhalation of short-acting β2-agonists in asthma patients tends to involve peripheral airways. This study shows that the heterogeneity of responses to short-acting β2-agonists in asthma not only involves distinct sites of bronchodilation, but also distinct sequences between these sites. This indicates that a detailed understanding of the bronchodilator effect of β2-agonists in asthma should not be limited to studying its early impact on FEV1.
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Affiliation(s)
- Lucas Demey
- Chest Department, Erasme University Hospital, Université libre de Bruxelles, Brussels, Belgium
| | - Alain Van Muylem
- Chest Department, Erasme University Hospital, Université libre de Bruxelles, Brussels, Belgium
| | - Andrei Malinovschi
- Department of Medical Sciences: Clinical Physiology, Uppsala University, Uppsala, Sweden
| | - Amaryllis Haccuria
- Chest Department, Erasme University Hospital, Université libre de Bruxelles, Brussels, Belgium
| | - Silvia Perez-Bogerd
- Chest Department, Erasme University Hospital, Université libre de Bruxelles, Brussels, Belgium
| | - Alain Michils
- Chest Department, Erasme University Hospital, Université libre de Bruxelles, Brussels, Belgium
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Arioglu-Inan E, Kayki-Mutlu G, Michel MC. Cardiac β 3 -adrenoceptors-A role in human pathophysiology? Br J Pharmacol 2019; 176:2482-2495. [PMID: 30801686 DOI: 10.1111/bph.14635] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 01/11/2019] [Accepted: 01/29/2019] [Indexed: 01/06/2023] Open
Abstract
As β3 -adrenoceptors were first demonstrated to be expressed in adipose tissue they have received much attention for their metabolic effects in obesity and diabetes. After the existence of this subtype had been suggested to be present in the heart, studies focused on its role in cardiac function. While the presence and functional role of β3 -adrenoceptors in the heart has not uniformly been detected, there is a broad consensus that they become up-regulated in pathological conditions associated with increased sympathetic activity such as heart failure and diabetes. When detected, the β3 -adrenceptor has been demonstrated to mediate negative inotropic effects in an inhibitory G protein-dependent manner through the NO-cGMP-PKG signalling pathway. Whether these negative inotropic effects provide protection from the adverse effects induced by overstimulation of β1 /β2 -adrenoceptors or in themselves are potentially harmful is controversial, but ongoing clinical studies in patients with congestive heart failure are testing the hypothesis that β3 -adrenceptor agonism has a beneficial effect. LINKED ARTICLES: This article is part of a themed section on Adrenoceptors-New Roles for Old Players. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.14/issuetoc.
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Affiliation(s)
- Ebru Arioglu-Inan
- Department of Pharmacology, Faculty of Pharmacy, Ankara University, Ankara, Turkey
| | - Gizem Kayki-Mutlu
- Department of Pharmacology, Faculty of Pharmacy, Ankara University, Ankara, Turkey
| | - Martin C Michel
- Department of Pharmacology, Johannes Gutenberg University, Mainz, Germany
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Varakantham V, Kurakula Sailoo AK, Nagalla B, Bharatraj DK. mRNA expression profile in peripheral blood mononuclear cells based on ADRB1 Ser49Gly and Arg389Gly polymorphisms in essential hypertension - a case-control pilot investigation in South Indian population. Clin Chem Lab Med 2018; 56:1230-1237. [PMID: 29750638 DOI: 10.1515/cclm-2017-0882] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Accepted: 12/05/2017] [Indexed: 11/15/2022]
Abstract
BACKGROUND β1-Adrenoreceptor (ADRB1) genetic polymorphisms are widely studied for susceptibility to many cardiovascular diseases such as essential hypertension. However, the mRNA expression of ADRB1 is rarely studied. METHODS A case-control pilot study with 292 hypertensives and 324 controls was designed to evaluate the role of the Ser49Gly and Arg389Gly, which are commonly studied single nucleotide polymorphisms (SNP), in the mRNA levels of ADRB1, in conjunction with its genetic predisposition to essential hypertension. RESULTS Differential expression of ADRB1 mRNA was seen between hypertensives and controls (p<0.01) based on genetic variants of Ser49Gly. Among hypertensive subjects, Ser49Ser and Gly49Gly were highly expressed in comparison to Ser49Gly (p<0.05 and p<0.01, respectively), whereas genetic variants of Arg389Gly did not demonstrate any such variations. We found no association between the ADRB1 SNPs viz., Ser49Gly and Arg389Gly and essential hypertension. CONCLUSIONS The increased mRNA levels of Gly49Gly may indicate a plausible role in the interindividual variations in drug response. Further, ADRB1 polymorphisms did not contribute to the genetic risk of essential hypertension. Studies with larger sample size are warranted to confirm these observations in the South Indian population.
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Affiliation(s)
- Varsha Varakantham
- Food and Drug Toxicology Research Centre, National Institute of Nutrition (Indian Council of Medical Research), Hyderabad, Telangana, India
| | | | - Balakrishna Nagalla
- Department of Biostatistics, National Institute of Nutrition (Indian Council of Medical Research), Hyderabad, Telangana, India
| | - Dinesh Kumar Bharatraj
- Food and Drug Toxicology Research Centre, National Institute of Nutrition (Indian Council of Medical Research), Hyderabad, Telangana, India
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Fang XY, Chen Z, Miao GB, Zhang L. Expression of β1- and β2-adrenergic receptors in the lungs and changes in the levels of corresponding autoantibodies in an aged rat model of heart failure. Int J Mol Med 2016; 38:1933-1939. [PMID: 27779651 DOI: 10.3892/ijmm.2016.2786] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Accepted: 10/11/2016] [Indexed: 11/06/2022] Open
Abstract
β-adrenergic receptors (β-ARs) and anti-β1-AR autoantibodies play important roles in heart failure. This study was designed to investigate the expression of β1- and β2-ARs in the lungs, and their relevance to the corresponding autoantibodies in an aged rat model of heart failure. In addition, we investigated the association between anti-β-AR autoantibody and soluble Fas (sFas) and soluble Fas ligand (sFasL). Aged male Wistar rats were divided into the sham-operated control group and the heart failure group. At 0 and 9 weeks post-surgery, the protein levels of β1- and β2-ARs in the heart and lungs were measured by western blot analysis. The plasma concentrations of autoantibodies, sFas and sFasL were determined by enzyme-linked immunosorbent assay (ELISA). The protein levels of pulmonary β1- and β2-ARs were decreased in the heart failure group when compared with the control group (P<0.01). Both the frequencies of the occurrence and the titers of autoantibodies against β2-AR increased at 9 weeks post-surgery (P<0.01). The levels of sFas and sFasL were also elevated, although there was no difference in the levels of sFas and sFasL between the groups, with positive and negative anti-β-AR autoantibody. These findings suggested that during the development of heart failure, the densities of pulmonary β1- and β2-ARs decreased. The levels of anti-β2-AR autoantibody exhibited similar changes as those of anti-β1-AR autoantibody, and there was no definite association between anti-β-AR autoantibody and the levels of sFas/sFasL.
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Affiliation(s)
- Xiang-Yang Fang
- Department of Internal Medicine, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, P.R. China
| | - Zhe Chen
- Department of Internal Medicine, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, P.R. China
| | - Guo-Bin Miao
- Heart Center, Beijing Tsinghua Changgung Hospital, Beijing 102218, P.R. China
| | - Lin Zhang
- Heart Center, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, P.R. China
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Benfante A, Basile M, Battaglia S, Spatafora M, Scichilone N. Use of ICS/LABA (extra-fine and non-extra-fine) in elderly asthmatics. Ther Clin Risk Manag 2016; 12:1553-1562. [PMID: 27789954 PMCID: PMC5072519 DOI: 10.2147/tcrm.s103709] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Age represents an exclusion criterion in randomized clinical trials designed to test the efficacy and safety of inhaled drugs in asthma. As a consequence, data on efficacy and safety of inhaled corticosteroid (ICS) and long-acting β2 agonist (LABA) combinations in elderly asthmatics are scanty. Older age is associated with an increased proportion of comorbid conditions; in addition, all organ functions undergo a process of senescence, thus reducing their ability to metabolize the agents. Overall, these age-associated conditions may variably, and often unpredictably, affect the metabolism and excretion of respiratory drugs. However, pharmacological treatment of asthma does not follow specific recommendations in the elderly. In the elderly, the ICS/LABA combinations may carry an increased risk of local indesiderable effects, primarily due to the lack of coordination between activation of the device and inhalation, and systemic adverse events, mainly due to the greater amount of active drug that is available because of the age-associated changes in organ functions as well as drug-to-drug and drug-to-concomitant disease interactions. The extra-fine formulations of ICSs/LABAs, which allow for a more favorable drug deposition in the lungs at a reduced dose, may contribute to overcome this issue. This review revises the efficacy and safety of treatment with ICSs/LABAs, focusing on the main pharmacodynamic and pharmacokinetic properties of the drugs and highlighting the potential risks in the elderly asthmatic population.
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Affiliation(s)
- Alida Benfante
- Biomedical Department of Internal and Specialist Medicine, University of Palermo, Palermo, Italy
| | - Marco Basile
- Biomedical Department of Internal and Specialist Medicine, University of Palermo, Palermo, Italy
| | - Salvatore Battaglia
- Biomedical Department of Internal and Specialist Medicine, University of Palermo, Palermo, Italy
| | - Mario Spatafora
- Biomedical Department of Internal and Specialist Medicine, University of Palermo, Palermo, Italy
| | - Nicola Scichilone
- Biomedical Department of Internal and Specialist Medicine, University of Palermo, Palermo, Italy
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Liebler JM, Borok Z, Li X, Zhou B, Sandoval AJ, Kim KJ, Crandall ED. Alveolar Epithelial Type I Cells Express β2-Adrenergic Receptors and G-protein Receptor Kinase 2. J Histochem Cytochem 2016; 52:759-67. [PMID: 15150284 DOI: 10.1369/jhc.3a6184.2004] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
β2-Adrenergic agonists stimulate alveolar epithelial sodium (Na+) transport and lung fluid clearance. Alveolar type II (AT2) cells have been reported to express β2-adrenergic receptors (β2AR). Given the large surface area covered by alveolar type I (AT1) cells and their potential role in alveolar fluid removal, we were interested in learning if AT1 cells express β2AR as well. Because β2AR is potentially susceptible to desensitization by G-protein-coupled receptor kinase 2 (GRK2), we also undertook localization of GRK2. β2AR and GRK2 expression was evaluated in whole lung, isolated alveolar epithelial cells (AECs), and AECs in primary culture, and was localized to specific AEC phenotypes by immunofluorescence techniques. β2AR is highly expressed in AT1 cells. β2AR mRNA increases with time in culture as AT2 cells transdifferentiate towards the AT1 cell phenotype. Immunoreactive GRK2 is seen in both AT1 and AT2 cells in similar amounts. These data suggest that both AT1 and AT2 cells may contribute to the increased alveolar Na+ and water clearance observed after exposure to β2 adrenergic agents. Both cell types also express GRK2, suggesting that both may undergo desensitization of β2AR with subsequent decline in the stimulatory effects of β2-adrenergic agonists over time.
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Affiliation(s)
- Janice M Liebler
- Will Rogers Institute Pulmonary Research Center, Division of Pulmonary and Critical Care Medicine, University of Southern California, Los Angeles, California 90033, USA.
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β2-Adrenoreceptor Agonist Inhalation During Ex Vivo Lung Perfusion Attenuates Lung Injury. Ann Thorac Surg 2015; 100:480-6. [DOI: 10.1016/j.athoracsur.2015.02.136] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Revised: 01/30/2015] [Accepted: 02/10/2015] [Indexed: 11/22/2022]
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Cazzola M, Page CP, Calzetta L, Matera MG. Pharmacology and therapeutics of bronchodilators. Pharmacol Rev 2012; 64:450-504. [PMID: 22611179 DOI: 10.1124/pr.111.004580] [Citation(s) in RCA: 307] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Bronchodilators are central in the treatment of of airways disorders. They are the mainstay of the current management of chronic obstructive pulmonary disease (COPD) and are critical in the symptomatic management of asthma, although controversies around the use of these drugs remain. Bronchodilators work through their direct relaxation effect on airway smooth muscle cells. at present, three major classes of bronchodilators, β(2)-adrenoceptor (AR) agonists, muscarinic receptor antagonists, and xanthines are available and can be used individually or in combination. The use of the inhaled route is currently preferred to minimize systemic effects. Fast- and short-acting agents are best used for rescue of symptoms, whereas long-acting agents are best used for maintenance therapy. It has proven difficult to discover novel classes of bronchodilator drugs, although potential new targets are emerging. Consequently, the logical approach has been to improve the existing bronchodilators, although several novel broncholytic classes are under development. An important step in simplifying asthma and COPD management and improving adherence with prescribed therapy is to reduce the dose frequency to the minimum necessary to maintain disease control. Therefore, the incorporation of once-daily dose administration is an important strategy to improve adherence. Several once-daily β(2)-AR agonists or ultra-long-acting β(2)-AR-agonists (LABAs), such as indacaterol, olodaterol, and vilanterol, are already in the market or under development for the treatment of COPD and asthma, but current recommendations suggest the use of LABAs only in combination with an inhaled corticosteroid. In addition, some new potentially long-acting antimuscarinic agents, such as glycopyrronium bromide (NVA-237), aclidinium bromide, and umeclidinium bromide (GSK573719), are under development, as well as combinations of several classes of long-acting bronchodilator drugs, in an attempt to simplify treatment regimens as much as possible. This review will describe the pharmacology and therapeutics of old, new, and emerging classes of bronchodilator.
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Affiliation(s)
- Mario Cazzola
- Università di Roma Tor Vergata, Dipartimento di Medicina Interna, Via Montpellier 1, 00133 Roma, Italy.
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Sakamoto J, Chen F, Nakajima D, Yamada T, Ohsumi A, Zhao X, Sakai H, Bando T, Date H. The effect of β-2 adrenoreceptor agonist inhalation on lungs donated after cardiac death in a canine lung transplantation model. J Heart Lung Transplant 2012; 31:773-9. [PMID: 22534458 DOI: 10.1016/j.healun.2012.03.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2011] [Revised: 03/06/2012] [Accepted: 03/27/2012] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND It is a matter of great importance in a donation after cardiac death to attenuate ischemia-reperfusion injury (IRI) related to the inevitable warm ischemic time. METHODS Donor dogs were rendered cardiac-dead and left at room temperature. The dogs were allocated into 2 groups: the β-2 group (n = 5) received an aerosolized β-2 adrenoreceptor agonist (procaterol, 350 μg) and ventilation with 100% oxygen for 60 minutes starting at 240 minutes after cardiac arrest, and the control group (n = 6) received an aerosolized control solvent with the ventilation. Lungs were recovered 300 minutes after cardiac arrest. Recipient dogs underwent left single-lung transplantation to evaluate the functions of the left transplanted lung for 240 minutes after the reperfusion. RESULTS Oxygenation and dynamic compliance were significantly higher in the β-2 group than in the control group. The β-2 group revealed significantly higher levels of cyclic adenosine monophosphate and high-energy phosphates in the donor lung after the inhalation than before it. Histologic findings revealed that the β-2 group had less edema and fewer inflammatory cells. CONCLUSION Our results suggest that β-2 adrenoreceptor agonist inhalation during the pre-procurement period may ameliorate IRI.
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Affiliation(s)
- Jin Sakamoto
- Department of Thoracic Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan
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Downs CA, Kriener LH, Yu L, Eaton DC, Jain L, Helms MN. β-Adrenergic agonists differentially regulate highly selective and nonselective epithelial sodium channels to promote alveolar fluid clearance in vivo. Am J Physiol Lung Cell Mol Physiol 2012; 302:L1167-78. [PMID: 22505670 DOI: 10.1152/ajplung.00038.2012] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
β-Adrenergic receptors (β-AR) increase epithelial sodium channel (ENaC) activity to promote lung fluid clearance. However, the effect of selective β-AR agonist on highly selective cation (HSC) channels or nonselective cation (NSC) channels in alveolar type 1 (T1) and type 2 (T2) cells is unknown. We hypothesized that stimulation with β(1)-AR agonist (denopamine) or β(2)-AR agonist (terbutaline) would increase HSC and/or NSC channel activity in alveolar epithelial cells. We performed single-channel measurements from T1 and T2 cells accessed from rat lung slices. Terbutaline (20 μM) increased HSC ENaC activity (open probability, NP(o)) in T1 (from 0.96 ± 0.61 to 1.25 ± 0.71, n = 5, P <0.05) and T2 cells (from 0.28 ± 0.14 to 1.0 ± 0.30, n = 8, P = 0.02). Denopamine (20 μM) increased NSC NP(o) in T1 cells (from 0.34 ± 0.09 to 0.63 ± 0.14, n = 7, P = 0.02) and in T2 cells (from 0.47 ± 0.09 to 0.68 ± 0.10, P = 0.004). In vivo X-ray imaging of lung fluid clearance and ICI 118,551 selective inhibition of β(2)-ARs confirmed patch-clamp findings. cAMP concentrations increased following treatment with denopamine or terbutaline (n = 3, P < 0.002). The effects of systemic (intraperitoneal, IP) and local (intratracheal, IT) modes of delivery on lung fluid clearance were assessed. IT delivery of denopamine promoted alveolar flooding, whereas IP delivery promoted delayed fluid clearance. In summary, β-AR agonists differentially regulate HSC and NSC in T1 and T2 cells to promote lung fluid clearance in vivo, and the mode of drug delivery is critical for maximizing β-AR agonist efficacy.
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Affiliation(s)
- Charles A Downs
- Department of Physiology, School of Medicine, Emory University, Atlanta, GA, USA
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Bossard F, Silantieff É, Lavazais-Blancou E, Robay A, Sagan C, Rozec B, Gauthier C. β1, β2, and β3 Adrenoceptors and Na+/H+Exchanger Regulatory Factor 1 Expression in Human Bronchi and Their Modifications in Cystic Fibrosis. Am J Respir Cell Mol Biol 2011; 44:91-8. [DOI: 10.1165/rcmb.2009-0372oc] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Novakova M, Kvetnansky R, Myslivecek J. Sexual dimorphism in stress-induced changes in adrenergic and muscarinic receptor densities in the lung of wild type and corticotropin-releasing hormone-knockout mice. Stress 2010; 13:22-35. [PMID: 20105053 DOI: 10.3109/10253890902849840] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We tested the hypothesis that single and repeated immobilization stress affect densities of alpha(1)-adrenoceptor (alpha(1)-AR) and beta-AR subtypes, muscarinic receptors (MR), adenylyl cyclase activity (AC) and phospholipase C activity (PLC) in lungs of male and female wild type (WT) and corticotropin-releasing hormone gene (CRH-knockout (KO)) disrupted mice. We found sex differences in the basal levels of alpha(1)-AR subtypes (females had 2-3 times higher density of receptors than males) and MR (males had twice the density found in females). In marked contrast, beta-AR subtype densities did not differ between sexes. CRH gene disruption decreased all three studied receptors in intact mice (to 20-50% of WT) in both sexes (except beta(1)-AR in females). Stress induced sexually dimorphic responses, while all alpha(1)-AR subtypes decreased in females (to 30% of control approximately), only alpha(1A)-AR level diminished (about 50%) in males. beta(1)-AR decreased in males (to about 40%) but remained stable in females. beta(2)-AR diminished in females (to about 20-60%) and also in males (to about 30-60%). MR decreased in both sexes (approximately to 50%). AC activity diminished in males (to < 50%) while PLC activity was not changed. In CRH-KO mice, the stress response was severely diminished. Paradoxically, the receptor response to stress was less affected by CRH-KO in males than in females. AC activity did not change in CRH-KO mice. In conclusion, in mice the stress reaction is sexually dimorphic and an intact hypothalamo-pituitary-adrenocortical system is required for the normal reaction of pulmonary adrenergic and MR to stress.
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Affiliation(s)
- Martina Novakova
- 1st Faculty of Medicine, Institute of Physiology, Charles University, Prague, Czech Republic
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Michel MC, Parra S. Similarities and differences in the autonomic control of airway and urinary bladder smooth muscle. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2008; 378:217-24. [PMID: 18548230 PMCID: PMC2493603 DOI: 10.1007/s00210-008-0316-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/03/2008] [Accepted: 05/17/2008] [Indexed: 11/25/2022]
Abstract
The airways and the urinary bladder are both hollow organs serving very different functions, i.e. air flow and urine storage, respectively. While the autonomic nervous system seems to play only a minor if any role in the physiological regulation of airway tone during normal breathing, it is important in the physiological regulation of bladder smooth muscle contraction and relaxation. While both tissues share a greater expression of M2 than of M3 muscarinic receptors, smooth muscle contraction in both is largely mediated by the smaller M3 population apparently involving phospholipase C activation to only a minor if any extent. While smooth muscle in both tissues can be relaxed by beta-adrenoceptor stimulation, this primarily involves beta2-adrenoceptors in human airways and beta3-adrenoceptors in human bladder. Despite activation of adenylyl cyclase by either subtype, cyclic adenosine monophosphate plays only a minor role in bladder relaxation by beta-agonists; an important but not exclusive function is known in airway relaxation. While airway beta2-adrenoceptors are sensitive to agonist-induced desensitization, beta3-adrenoceptors are generally considered to exhibit much less if any sensitivity to desensitization. Gene polymorphisms exist in the genes of both beta2- and beta3-adrenoceptors. Despite being not fully conclusive, the available data suggest some role of beta2-adrenoceptor polymorphisms in airway function and its treatment by receptor agonists, whereas the available data on beta3-adrenoceptor polymorphisms and bladder function are too limited to allow robust interpretation. We conclude that the distinct functions of airways and urinary bladder are reflected in a differential regulation by the autonomic nervous system. Studying these differences may be informative for a better understanding of each tissue.
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Affiliation(s)
- Martin C Michel
- Department Pharmacology and Pharmacotherapy, Academic Medical Center, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands.
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Current issues with beta2-adrenoceptor agonists: pharmacology and molecular and cellular mechanisms. Clin Rev Allergy Immunol 2007; 31:119-30. [PMID: 17085788 DOI: 10.1385/criai:31:2:119] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/1999] [Revised: 11/30/1999] [Accepted: 11/30/1999] [Indexed: 11/11/2022]
Abstract
Beta2-adrenoceptors are widely, almost ubiquitously, expressed. Activation of these receptors on bronchial smooth muscle by short- and long-acting beta2-adrenoceptor agonists causes bronchodilation. Here, the beta2-adrenoceptor is linked by the G protein, Gs, to adenylyl cyclase, which increases cyclic adenosine monophosphate (cAMP), thus activating protein kinase A, which affects calcium levels and reduces the efficiency of myosin light-chain kinase, causing relaxation. Activation also entrains numerous acute and longer term downregulation responses affecting the number, location, and net efficiency of signaling of the receptor. Synthetic beta2-agonists are all "partial agonists," incompletely able to optimally stimulate cAMP signal transduction. However, compared with some cells (such as mast cells) involved in exercise- induced asthma induction, airway smooth muscle is privileged in that transduction efficiency is intrinsically high and the tissue is very resistant to complete downregulation. Glucocorticosteroids have broadly beneficial interactions with beta2-adrenoceptors. Researchers have recently discovered that the beta2-adrenoceptor may function as a homodimer and that it can form heterodimers with both the beta1- and beta3-adrenoceptors, and possibly other receptors. This further complicates interpretation of the effect of beta2-adrenoceptor polymorphisms, but it is unknown whether this occurs in humans in vivo. Researchers have known for some time that strong contraction involving receptors coupled to the Gq G protein (e.g., cholinergic and leukotriene receptors via negative biochemical crosstalk), virus infection (via uncoupling), and inflammation (via kinases) can impair relaxation. Most recently, researchers have discovered that the beta2-adrenoceptor can also send potentially adverse signals after "atypical coupling" to Gq rather than Gs. The clinical implications of these uncouplings, crosstalk, and atypical coupling possibilities are not well-understood.
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Abraham G, Kottke C, Dhein S, Ungemach FR. Pharmacological and biochemical characterization of the beta-adrenergic signal transduction pathway in different segments of the respiratory tract. Biochem Pharmacol 2003; 66:1067-81. [PMID: 12963495 DOI: 10.1016/s0006-2952(03)00460-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Although in the respiratory system there is great therapeutic interest in manipulating and understanding the beta-adrenoceptor-G-protein-adenylate cyclase (AC) signal transduction pathway, little is known on segmental differences among lung, bronchus, and trachea with regard to the receptor concentration and interaction to G-proteins and coupling to AC. In this study, patterns of distribution and absolute quantities of beta-adrenoceptor subtypes beta(1) and beta(2) were determined in membranes of equine lung parenchyma, bronchial and tracheal epithelium with the underlying smooth muscle by saturation and competition binding assays using the radioligand (-)-[125I]-iodocyanopindolol (ICYP). Additionally, the functional coupling of beta-adrenoceptors to G-proteins (assessed by beta-agonist competition binding in the presence and absence of GTP) as well as the coupling efficiency and biochemical activities of AC was investigated in each region. The specific ICYP binding was rapid, reversible, saturable with time and of high affinity. The radioligand binding identified more total beta-adrenoceptors in the lung than in bronchus or trachea (428+/-19, 162.4+/-4.8, 75.6+/-1.2 fmol/mg protein, respectively) with about 40% of receptors in the high affinity state. The beta(2)-adrenoceptor subtype predominated in all segments (approximately 74-80%), as the highly selective beta(2)-adrenoceptor antagonist ICI 118,551 was about 10,000 times more potent in inhibiting ICYP binding than was the beta(1)-selective adrenoceptor antagonist CGP 20712A, and beta-adrenoceptor agonists inhibited ICYP binding with an order of potency: (-)-isoprenaline>(-)-adrenaline>(-)-noradrenaline. The dissociation constant (K(d)) was higher in the trachea than in bronchus or lung (13.0+/-0.9 pM vs. 20.0+/-2.3 pM vs. 30.8+/-4.4 pM, P<0.05, respectively). The beta(2)-adrenoceptor-mediated AC response was tissue-dependent; stimulants acting on beta-adrenoceptor (isoproterenol), G-protein (GTP, NaF) and AC (forskolin, Mn(2+)) enhanced AC responses in all three regions, but the AC activity was higher in tracheal crude membranes than in bronchus or lung (trachea>>>bronchus>lung), hence, the number of beta(2)-adrenoceptors correlated inversely with the amount of AC. We conclude that (1) the stoichiometry of components within the pulmonary beta-adrenoceptor-G-protein complex is segment-dependent, and (2) the receptor number or AC activity is possibly the rate-limiting factor in the beta-adrenoceptor-G-protein-AC-mediated physiological responses. Thus, it is speculated that this could have important therapeutic consequences in beta-adrenoceptor agonist-induced receptor regulation in bronchial asthma.
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Affiliation(s)
- Getu Abraham
- Faculty of Veterinary Medicine, Institute of Pharmacology, Pharmacy and Toxicology, Leipzig University, An den Tierkliniken 15, 04103 Leipzig, Germany.
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Hislop AA, Mak JCW, Kelly D, Reader JA, Barnes PJ, Haworth SG. Postnatal changes in beta-adrenoceptors in the lung and the effect of hypoxia induced pulmonary hypertension of the newborn. Br J Pharmacol 2002; 135:1415-24. [PMID: 11906954 PMCID: PMC1573262 DOI: 10.1038/sj.bjp.0704597] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. beta-adrenoceptor activation leads to pulmonary vasodilatation. The increase in circulating catecholamines at birth may assist the postnatal fall in vascular resistance by their activation. To study beta(1)- and beta(2)-adrenoceptors during postnatal adaptation, we used [(125)I]-iodocyanopindolol (ICYP) binding to lung membranes and sections to quantify and locate the binding sites in piglets from birth to 14 days of age and compared them with those in adult pigs. In addition, pulmonary hypertension was induced in newborn piglets by hypobaric hypoxia. 2. In lung membranes the equilibrium dissociation constant (K(d)) did not change with age for total beta-adrenoceptors or for beta(2)-adrenoceptors, but there was a significant increase in maximum binding sites (B(max)) between birth and 3 days of age. On tissue sections, B(max) increased between 3 days and adulthood with no change in K(d). 3. Binding sites of beta(1)- and beta(2)-adrenoceptors were localized to the bronchial epithelium, to endothelium of extra- and intra-pulmonary arteries and to lung parenchyma. Total beta-adrenoceptor density increased with age at all locations (P<0.05 - 0.01). At birth intrapulmonary arteries showed no binding, beta(2)-adrenoceptors appeared on day 1 and increased up to 14 days of age. beta(1)-adrenoceptors appeared by 3 days of age and increased with age. 4. Hypobaric hypoxia from birth led to attenuation in the normal postnatal increase in receptor number, but hypoxia from 3 - 6 days did not decrease receptor density. 5. The normal postnatal increase in beta-adrenoceptors suggests a potential for catecholamine induced dilatation in the lung during adaptation which is attenuated in pulmonary hypertension.
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Affiliation(s)
- Alison A Hislop
- Vascular Biology and Pharmacology Unit, Institute of Child Health, London, UK.
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Naline E, Bardou M, Devillier P, Molimard M, Dumas M, Chalon P, Manara L, Advenier C. Inhibition by SR 59119A of isoprenaline-, forskolin- and VIP-induced relaxation of human isolated bronchi. Pulm Pharmacol Ther 2000; 13:167-74. [PMID: 10930355 DOI: 10.1006/pupt.2000.0246] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In the human isolated bronchus (HIB) it has been shown that beta(3)-adrenoceptor stimulation fails to induce relaxation of airway smooth muscle. It has however been reported in human ventricular endomyocardial biopsies that beta(3)-adrenoceptor stimulation induced a marked negative inotropic effect which could be linked to Gi protein activation. The aims of this study were: (1) to determine in HIB (internal diameter 1-2 mm) whether the selective beta(3)-adrenoceptor agonist SR 59119A (N[7-methoxy-1,2,3, 4-tetrahydronaphthalen-(2R)methyl]-(2R)-2-hydroxy-2-(3-chloroph eny l)e thanamine hydrochloride) was able to inhibit adenylate-cyclase-mediated airway smooth muscle relaxation induced by isoprenaline, forskolin or vasoactive intestinal peptide (VIP) and (2) to investigate the role of the Gi protein in this interaction. SR 59119A (0.1 microM and 1 microM) induced a shift to the right of concentration response curve for isoprenaline (-0. 15+/-0.06 and -0.54+/-0.21 log unit, P<0.05 and P<0.01 respectively), forskolin (-0.12+/-0.02 and -0.30+/-0.05 log unit, P<0.001), and VIP (-0.42+/-0.12 log unit, P<0.01 with SR59119A 10(-6)M). The inhibitory effect of SR 59119A was (1) abolished by an incubation of HIB with pertussis toxin (1 microg/ml, during 15 h in Krebs-Henseleit solution, at 21 degrees C), which is known to inactivate the Gi protein and (2) increased after an incubation of HIB with the pro-inflammatory cytokine IL-1beta (10 ng/ml, during 15 h in Krebs-Henseleit solution, at 21 degrees C), which is known to up-regulate Gi protein expression. Our results suggest that the selective beta(3)-adrenoceptor agonist SR59119A might inhibit the cAMP-dependent relaxation of human isolated bronchus through Gi protein-mediated inhibition of adenylate cyclase.
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Affiliation(s)
- E Naline
- Département de Pharmacologie, Faculté de Médecine Paris-Ouest, 15 Rue de Lécole de Médecine, Paris, France
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Bardou M, Loustalot C, Cortijo J, Simon B, Naline E, Dumas M, Esteve S, Croci T, Chalon P, Frydman R, Sagot P, Manara L, Morcillo EJ, Advenier C. Functional, biochemical and molecular biological evidence for a possible beta(3)-adrenoceptor in human near-term myometrium. Br J Pharmacol 2000; 130:1960-6. [PMID: 10952688 PMCID: PMC1572258 DOI: 10.1038/sj.bjp.0703491] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The possible existence of a beta(3)-adrenoceptor (beta(3)-AR) in human near-term myometrium was investigated by in vitro functional and biochemical studies and analysis of mRNA expression. SR 59119A and SR 59104A and CGP 12177 (two selective agonists and a partial agonist, respectively, of the beta(3)-AR), salbutamol and terbutaline (beta(2)-AR agonists) each produced a concentration-dependent relaxation of the myometrial spontaneous contractions. There were no differences in pD(2) values for the relaxing potencies of terbutaline, salbutamol, CGP 12177 and SR 59119A. The rank order for their relaxing efficacies was SR 59119A>SR 59104A>terbutaline approximately salbutamol approximately CGP 12177 (E(max)=52+/-7%, 42+/-12% and approximately 30% respectively). Propranolol, a beta(1)- and beta(2)-AR antagonist, and ICI 118551, a beta(2)-AR antagonist (both at 0.1 microM), did not affect the SR 59119A-induced relaxation whereas SR 59230A, a selective beta(3)-AR antagonist (1 microM), significantly reduced the maximal relaxing effect of SR 59119A. SR 59119A and salbutamol induced a significant increase in cyclic AMP levels that was antagonized by SR 59230A but not by propranolol for SR 59119A, and by propranolol but not by SR 59230A for salbutamol. The beta(3)-AR mRNA was positively expressed in myometrium preparations in a reverse transcription polymerase chain assay. The results presented provide the first evidence for the existence of the beta(3)-AR subtype in human near-term myometrium and suggest that the effects of SR 59119A might be mediated through an increase in cyclic AMP level.
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Affiliation(s)
- M Bardou
- Department of Pharmacology, Faculty of Medicine Paris-Ouest, 15 rue de l'Ecole de Médecine 75006 Paris, France.
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Zhang H, Kim YK, Govindarajan A, Baba A, Binnie M, Marco Ranieri V, Liu M, Slutsky AS. Effect of adrenoreceptors on endotoxin-induced cytokines and lipid peroxidation in lung explants. Am J Respir Crit Care Med 1999; 160:1703-10. [PMID: 10556144 DOI: 10.1164/ajrccm.160.5.9903068] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Lung tissue may be an important source of systemic inflammation associated with sepsis and the acute respiratory distress syndrome (ARDS). An ex vivo model of freshly explanted lung tissue in culture was developed to evaluate the ability of lipopolysaccharide (LPS) to directly stimulate lung tissues under conditions where indirect mechanisms such as recruitment of blood-derived inflammatory cells could not be implicated. Under control conditions, lung explants produced a high level of macrophage inflammatory protein-2 (MIP-2). Eight hours after LPS challenge, there were marked increases in the production of tumor necrosis factor-alpha (TNF-alpha) from 0.18 +/- 0.04 to 4.13 +/- 0.23 ng/ml/g tissue (p < 0.05), MIP-2 from 60.0 +/- 7.4 to 165.6 +/- 10.3 ng/ml/g tissue (p < 0.05), and tissue lipid peroxidation (malonaldehyde from 27.6 +/- 2.5 to 48.4 +/- 17.5 microM/g tissue; and 4-hydroxyalkenal from 34.0 +/- 3.0 to 59.7 +/- 18.8 microM/g tissue, both p < 0.05) from lung explants. Treatment with the beta-adrenoreceptor agonist isoproterenol (1 ng/ml) attenuated LPS-induced release of TNF-alpha and lipid peroxidation in association with an increase in intracellular cAMP levels. The adenylate cyclase activator, forskolin, also inhibited LPS-induced changes in TNF-alpha and lipid peroxidation. In conclusion, increasing intracellular levels of cAMP through beta-adrenoreceptor activation can attenuate the acute inflammatory response induced in the lung by LPS. LPS did not significantly impair the beta-adrenoreceptor reactivity in lung explants. Lung explants allow for the quantitative assessment of pulmonary inflammatory responses independent of influences from the circulation, and thus may be a useful ex vivo model to investigate cellular and molecular mechanisms of lung injury.
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Affiliation(s)
- H Zhang
- Division of Respiratory Medicine, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Toronto, Ontario, Canad.
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Abstract
Surfactant secretion is a critical regulated process in the metabolism of pulmonary surfactant. Presumably, because this process is vital to the survival of the organism, there are several independent pathways for stimulating secretion which work through different cell surface receptors and signaling mechanisms. In addition, there is apparent homeostatic regulation in that two components of surfactant, namely SP-A and dipalmitoylphosphatidylcholine, can inhibit secretion. Although secretion of surfactant has been studied for over two decades, there remains some important issues to be resolved. In vivo secretion can be stimulated by hyperventilation or even a single large breath. However, we do not know the biochemical mechanism for this physiologically important form of stimulation. In vitro, we know many of the proximal events in signaling, but we do not know how the lamellar bodies move within a cell or the docking mechanism at the plasma membrane. Many investigators have demonstrated that SP-A will inhibit secretion in vitro, but the mechanism is not known. Finally, there is a route of secretion of SP-A independent of lamellar bodies, but we do not know details of this pathway nor its regulation.
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Affiliation(s)
- R J Mason
- Department of Medicine, National Jewish Medical and Research Center, 1400 Jackson Street, Denver, CO 80206, USA.
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