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Hollenhorst MI, Jurastow I, Nandigama R, Appenzeller S, Li L, Vogel J, Wiederhold S, Althaus M, Empting M, Altmüller J, Hirsch AKH, Flockerzi V, Canning BJ, Saliba A, Krasteva‐Christ G. Tracheal brush cells release acetylcholine in response to bitter tastants for paracrine and autocrine signaling. FASEB J 2019; 34:316-332. [DOI: 10.1096/fj.201901314rr] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 10/20/2019] [Accepted: 10/22/2019] [Indexed: 12/20/2022]
Affiliation(s)
| | - Innokentij Jurastow
- Institute of Anatomy and Cell Biology Justus‐Liebig‐University of Giessen Giessen Germany
- Department of Anesthesiology and Intensive Care Medicine (CS) University Hospital Charité Humboldt University of Berlin Berlin Germany
| | - Rajender Nandigama
- Institute of Anatomy and Cell Biology University of Würzburg Würzburg Germany
| | - Silke Appenzeller
- Comprehensive Cancer Centre Mainfranken University of Würzburg Würzburg Germany
| | - Lei Li
- Core Unit SysMed University of Würzburg Würzburg Germany
| | - Jörg Vogel
- Helmholtz Institute for RNA‐based Infection Research (HIRI) Helmholtz‐Centre for Infection Research (HZI) Würzburg Germany
| | - Stephanie Wiederhold
- Institute of Anatomy and Cell Biology Justus‐Liebig‐University of Giessen Giessen Germany
| | - Mike Althaus
- School of Natural and Environmental Sciences Newcastle University Newcastle upon Tyne United Kingdom
| | - Martin Empting
- Department of Drug Design and Optimization (DDOP) Helmholtz‐Institute for Pharmaceutical Research Saarland (HIPS)‐Helmholtz Centre for Infection Research (HZI) Saarbrücken Germany
- Department of Pharmacy Saarland University Saarbrücken Germany
- German Centre for Infection Research (DZIF) Saarbrücken Germany
| | - Janine Altmüller
- Cologne Centre for Genomics University of Cologne Cologne Germany
| | - Anna K. H. Hirsch
- Department of Drug Design and Optimization (DDOP) Helmholtz‐Institute for Pharmaceutical Research Saarland (HIPS)‐Helmholtz Centre for Infection Research (HZI) Saarbrücken Germany
- Department of Pharmacy Saarland University Saarbrücken Germany
- German Centre for Infection Research (DZIF) Saarbrücken Germany
| | - Veit Flockerzi
- Institute of Experimental and Clinical Pharmacology and Toxicology/PZMS Saarland University Homburg Germany
| | - Brendan J. Canning
- Department of Medicine Division of Allergy and Clinical Immunology School of Medicine Johns Hopkins University Baltimore MD USA
| | - Antoine‐Emmanuel Saliba
- Helmholtz Institute for RNA‐based Infection Research (HIRI) Helmholtz‐Centre for Infection Research (HZI) Würzburg Germany
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Agarwal R, Dhooria S, Aggarwal AN, Maturu VN, Sehgal IS, Muthu V, Prasad KT, Yenge LB, Singh N, Behera D, Jindal SK, Gupta D, Balamugesh T, Bhalla A, Chaudhry D, Chhabra SK, Chokhani R, Chopra V, Dadhwal DS, D’Souza G, Garg M, Gaur SN, Gopal B, Ghoshal AG, Guleria R, Gupta KB, Haldar I, Jain S, Jain NK, Jain VK, Janmeja AK, Kant S, Kashyap S, Khilnani GC, Kishan J, Kumar R, Koul PA, Mahashur A, Mandal AK, Malhotra S, Mohammed S, Mohapatra PR, Patel D, Prasad R, Ray P, Samaria JK, Singh PS, Sawhney H, Shafiq N, Sharma N, Sidhu UPS, Singla R, Suri JC, Talwar D, Varma S. Guidelines for diagnosis and management of bronchial asthma: Joint ICS/NCCP (I) recommendations. Lung India 2015; 32:S3-S42. [PMID: 25948889 PMCID: PMC4405919 DOI: 10.4103/0970-2113.154517] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Affiliation(s)
- Ritesh Agarwal
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Sahajal Dhooria
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Ashutosh Nath Aggarwal
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Venkata N Maturu
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Inderpaul S Sehgal
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Valliappan Muthu
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Kuruswamy T Prasad
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Lakshmikant B Yenge
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Navneet Singh
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Digambar Behera
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Surinder K Jindal
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Dheeraj Gupta
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Thanagakunam Balamugesh
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Ashish Bhalla
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Dhruva Chaudhry
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Sunil K Chhabra
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Ramesh Chokhani
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Vishal Chopra
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Devendra S Dadhwal
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - George D’Souza
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Mandeep Garg
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Shailendra N Gaur
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Bharat Gopal
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Aloke G Ghoshal
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Randeep Guleria
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Krishna B Gupta
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Indranil Haldar
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Sanjay Jain
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Nirmal K Jain
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Vikram K Jain
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Ashok K Janmeja
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Surya Kant
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Surender Kashyap
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Gopi C Khilnani
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Jai Kishan
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Raj Kumar
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Parvaiz A Koul
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Ashok Mahashur
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Amit K Mandal
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Samir Malhotra
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Sabir Mohammed
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Prasanta R Mohapatra
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Dharmesh Patel
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Rajendra Prasad
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Pallab Ray
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Jai K Samaria
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Potsangbam Sarat Singh
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Honey Sawhney
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Nusrat Shafiq
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Navneet Sharma
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Updesh Pal S Sidhu
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Rupak Singla
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Jagdish C Suri
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Deepak Talwar
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
| | - Subhash Varma
- Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research (PGIMER), Indian Chest Society and National College of Chest Physicians, Chandigarh, Punjab, India
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Harvey BC, Parameswaran H, Lutchen KR. Can tidal breathing with deep inspirations of intact airways create sustained bronchoprotection or bronchodilation? J Appl Physiol (1985) 2013; 115:436-45. [PMID: 23722710 DOI: 10.1152/japplphysiol.00009.2013] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Fluctuating forces imposed on the airway smooth muscle due to breathing are believed to regulate hyperresponsiveness in vivo. However, recent animal and human isolated airway studies have shown that typical breathing-sized transmural pressure (Ptm) oscillations around a fixed mean are ineffective at mitigating airway constriction. To help understand this discrepancy, we hypothesized that Ptm oscillations capable of producing the same degree of bronchodilation as observed in airway smooth muscle strip studies requires imposition of strains larger than those expected to occur in vivo. First, we applied increasingly larger amplitude Ptm oscillations to a statically constricted airway from a Ptm simulating normal functional residual capacity of 5 cmH2O. Tidal-like oscillations (5-10 cmH2O) imposed 4.9 ± 2.0% strain and resulted in 11.6 ± 4.8% recovery, while Ptm oscillations simulating a deep inspiration at every breath (5-30 cmH2O) achieved 62.9 ± 12.1% recovery. These same Ptm oscillations were then applied starting from a Ptm = 1 cmH2O, resulting in approximately double the strain for each oscillation amplitude. When extreme strains were imposed, we observed full recovery. On combining the two data sets, we found a linear relationship between strain and resultant recovery. Finally, we compared the impact of Ptm oscillations before and after constriction to Ptm oscillations applied only after constriction and found that both loading conditions had a similar effect on narrowing. We conclude that, while sufficiently large strains applied to the airway wall are capable of producing substantial bronchodilation, the Ptm oscillations necessary to achieve those strains are not expected to occur in vivo.
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Affiliation(s)
- Brian C Harvey
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts 02215, USA.
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Berk M, Kapczinski F, Andreazza AC, Dean OM, Giorlando F, Maes M, Yücel M, Gama CS, Dodd S, Dean B, Magalhães PVS, Amminger P, McGorry P, Malhi GS. Pathways underlying neuroprogression in bipolar disorder: focus on inflammation, oxidative stress and neurotrophic factors. Neurosci Biobehav Rev 2010; 35:804-17. [PMID: 20934453 DOI: 10.1016/j.neubiorev.2010.10.001] [Citation(s) in RCA: 856] [Impact Index Per Article: 61.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2010] [Revised: 09/29/2010] [Accepted: 10/01/2010] [Indexed: 12/11/2022]
Abstract
There is now strong evidence of progressive neuropathological processes in bipolar disorder (BD). On this basis, the current understanding of the neurobiology of BD has shifted from an initial focus on monoamines, subsequently including evidence of changes in intracellular second messenger systems and more recently to, incorporating changes in inflammatory cytokines, corticosteroids, neurotrophins, mitochondrial energy generation, oxidative stress and neurogenesis into a more comprehensive model capable of explaining some of the clinical features of BD. These features include progressive shortening of the inter-episode interval with each recurrence, occurring in consort with reduced probability of treatment response as the illness progresses. To this end, emerging data shows that these biomarkers may differ between early and late stages of BD in parallel with stage-related structural and neurocognitive alterations. This understanding facilitates identification of rational therapeutic targets, and the development of novel treatment classes. Additionally, these pathways provide a cogent explanation for the efficacy of seemingly diverse therapies used in BD, that appear to share common effects on oxidative, inflammatory and neurotrophic pathways.
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Affiliation(s)
- M Berk
- Department of Clinical and Biomedical Sciences, University of Melbourne, Victoria 3010, Australia.
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Baroffio M, Crimi E, Brusasco V. Airway smooth muscle as a model for new investigative drugs in asthma. Ther Adv Respir Dis 2009; 2:129-39. [PMID: 19124365 DOI: 10.1177/1753465808091154] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Bronchial asthma as such exists because airway smooth muscle (ASM) contracts excessively in response to various stimuli. After several decades during which research was mainly focused on airway inflammation, increasing attention is now being paid to a possible abnormal behaviour of ASM. Thus, ASM is regarded as a major target for anti-asthma treatments. This review first describes the mechanisms of ASM contraction and airway hyperresponsiveness, through cellular, animal and human models. The developments of new drugs targeting extra and/or intracellular pathway of ASM contraction are discussed.
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Affiliation(s)
- Michele Baroffio
- Dipartimento di Medicina Interna, Università di Genova, Viale Benedetto XV, 6, 16132 Genova, Italy
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6
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Alexia J, Lewis CA, Broadley KJ. EFFECTS OF LOW-LEVEL OZONE EXPOSURE ON REACTIVITY AND CONDUCTANCE IN GUINEA PIG AIRWAYS. Inhal Toxicol 2008. [DOI: 10.1080/089583798197808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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7
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Musk AWB, James AL, Palmer LJ, Ryan GF, Lake F, Golledge CL, De Klerk NH. Respiratory infections and lung function in an Australian Aboriginal community. Respirology 2008; 13:257-62. [PMID: 18339025 PMCID: PMC7192217 DOI: 10.1111/j.1440-1843.2007.01221.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2007] [Revised: 06/26/2007] [Accepted: 07/10/2007] [Indexed: 11/29/2022]
Abstract
BACKGROUND AND OBJECTIVE To investigate the association between serological evidence of past infections with common respiratory pathogens and lung function in members of an isolated community of Aborigines from tropical coastal north-western Australia. METHODS FEV(1) and FVC were assessed by dry bellows spirometer. Serum IgG titres to 11 common respiratory pathogens were assayed. Smoking history was assessed by questionnaire. Reciprocal positive IgG titres were taken as >or=10 for all pathogens with the exception of Legionella spp. (>or=40) and Burkholderia pseudomallei (>or=20). Linear regression analysis examined associations between titres and lung function after adjustment for age, height, gender and smoking, separately for adults (age > 17 years) and children. RESULTS An increased total number of positive IgG titres was significantly associated with reduced FEV(1) (P = 0.01) and FEV(1)/FVC ratio (P = 0.01) suggesting the presence of airflow obstruction. This association was independent of age, gender, height, weight and smoking status. CONCLUSIONS The burden of past respiratory infections may be an important determinant of airway function in this Aboriginal community.
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Affiliation(s)
- A W Bill Musk
- Department of Respiratory Medicine, Sir Charles Gairdner Hospital, Nedlands, WA 6009, Australia.
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Ekelund M, Kristensson E, Ekelund M, Ekblad E. Total parenteral nutrition causes circumferential intestinal atrophy, remodeling of the intestinal wall, and redistribution of eosinophils in the rat gastrointestinal tract. Dig Dis Sci 2007; 52:1833-9. [PMID: 17390221 DOI: 10.1007/s10620-006-9678-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2006] [Accepted: 11/07/2006] [Indexed: 12/09/2022]
Abstract
Total parenteral nutrition (TPN) is held to cause intestinal atrophy and weaken mechanical and immunological barriers. To monitor the degree of atrophy caused by TPN, female Sprague-Dawley rats were, for 8 days, maintained on TPN (n = 6) and compared to identically housed controls given food and water ad libitum (n = 6). Specimens from jejunum, ileum, and colon were taken for histology and morphometric analysis. Topographic distribution and presence of eosinophils, by eosinophil peroxidase (EPO) staining, were examined in the gastric fundus, jejunum, ileum, and colon. Atrophy in terms of a markedly reduced circumference was noted throughout the intestinal tract in all rats subjected to TPN. The width of jejunal and ileal villi was narrowed and the length of jejunal villi was decreased. Furthermore, submucosal thickness in the jejunum and ileum increased. The height of ileal enterocytes remained unaltered. The number of goblet cells decreased in jejunal but not in ileal villi. The Paneth cells, suggested to play important roles in innate defense, increased in size. In the gastric fundus a marked increase in eosinophils was revealed predominantly in the mucosa and submucosa. The number and distribution of jejunal and ileal eosinophils were identical to those of controls. In colon from TPN rats, a redistribution of eosinophils was noted, causing a "band-like" accumulation of eosinophils in the basal portion of the mucosa. In conclusion, TPN causes gut atrophy and an increase in Paneth cell size. Eosinophils increase in number in the gastric fundus and a topographic redistribution occurs in the colon.
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Affiliation(s)
- Mikael Ekelund
- Department of Surgery, Clinical Sciences, Lund University, SE-221 85, Lund, Sweden.
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Ricci A, Mariotta S, Amenta F, Tayebati SK, Terzano C. Changes in muscarinic cholinergic receptor expression in human peripheral blood lymphocytes in allergic rhinitis patients. Pulm Pharmacol Ther 2007; 21:79-87. [PMID: 17360208 DOI: 10.1016/j.pupt.2006.12.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2006] [Revised: 11/20/2006] [Accepted: 12/19/2006] [Indexed: 11/19/2022]
Abstract
BACKGROUND Parasympathetic nerves provide the dominant autonomic innervation of the upper and lower airways. They release acetylcholine that, activating post-junctional muscarinic receptors, causes bronchoconstriction, mucous secretion and vasodilation. Dysfunction of the upper and lower airways frequently coexist, and they appear to share key elements of pathogenesis. OBJECTIVE The present study has assessed the expression and pattern of cholinergic muscarinic receptor subtypes in peripheral blood lymphocytes harvested from allergic rhinitis patients with different degree of bronchial hyperresponsiveness detected by methacholine challenge test. METHODS Radioligand binding assay for determining the density of muscarinic cholinergic receptor subtypes; immunoblot analysis for assessing the characteristic of muscarinic cholinergic receptor subtype protein and immunocytochemical techniques for investigating the cellular localization of receptors. RESULTS An increased expression of M2 and M5 receptor proteins was observed in peripheral blood lymphocytes of allergic rhinitis patients in comparison with healthy control individuals. M3 receptor subtype decreased in allergic rhinitis patients with normal or mild responses to methacholine. A trend versus a return to normal value was found in moderate and severe responders. No changes of the M4 receptor subtype were found. CONCLUSIONS AND CLINICAL IMPLICATIONS Increase in M2 receptor expression correlated with disease severity and bronchial hyperreactivity. Changes in muscarinic cholinergic receptor expression in allergic rhinitis underline a role of cholinergic system of immune cells in allergic airway disease. CAPSULE SUMMARY Studies addressed to rhinitis and asthma have identified many similarities. Our results indicate that changes in peripheral blood lymphocyte muscarinic receptor expression may reflect the cholinergic involvement into allergic airway diseases.
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Affiliation(s)
- Alberto Ricci
- Dipartimento di Scienze Cardiovascolari e Respiratorie, Università di Roma La Sapienza, Rome, Italy
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Kanazawa H. Anticholinergic agents in asthma: chronic bronchodilator therapy, relief of acute severe asthma, reduction of chronic viral inflammation and prevention of airway remodeling. Curr Opin Pulm Med 2006; 12:60-7. [PMID: 16357581 DOI: 10.1097/01.mcp.0000198066.73328.3a] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW It is difficult to identify specific groups of asthmatic patients who may benefit from acute or chronic use of anticholinergic agents. Therefore, an important consideration is how anticholinergic agents can be used to achieve clinically effective treatment of asthma. RECENT FINDINGS A genotype-stratified study revealed that greater bronchoprotective effect of anticholinergic agents was observed in asthmatic patients with the Arg/Arg genotype of the beta2-adrenergic receptor. Anticholinergic agents could add to the bronchodilation obtained with beta2-agonists on acute severe asthma. CD8+ T lymphocytes induced by chronic hepatitis C viral infection causes chronic obstructive pulmonary disease-like inflammation in asthma. Virus-specific CD8+ T lymphocytes may induce cholinergic activation in asthma through M2 receptor dysfunction. Therefore, anticholinergic agents are highly effective for asthma associated with chronic viral infection. In contrast, asthma with chronic obstructive pulmonary disease-like inflammation appears to be poorly responsive to beta2-agonists and can lead to partially irreversible airflow limitation. Moreover, a recent report suggested that treatment with inhaled tiotropium bromide markedly inhibited the increase in airway smooth muscle mass, myosin expression, and contractility in asthma. SUMMARY Anticholinergic agents may benefit stable asthmatics, particularly those who have the Arg/Arg genotype. These agents have a demonstrated role in combination with beta2-agonists in the treatment of acute severe asthma, and may benefit asthmatics with chronic obstructive pulmonary disease-like inflammation. Moreover, these agents could be also beneficial in preventing airway remodeling in asthmatic airways.
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Affiliation(s)
- Hiroshi Kanazawa
- Department of Respiratory Medicine, Graduate School of Medicine, Osaka City University, Asahi-machi, Abenoku, Osaka, Japan.
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11
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Walker JKL, Gainetdinov RR, Feldman DS, McFawn PK, Caron MG, Lefkowitz RJ, Premont RT, Fisher JT. G protein-coupled receptor kinase 5 regulates airway responses induced by muscarinic receptor activation. Am J Physiol Lung Cell Mol Physiol 2003; 286:L312-9. [PMID: 14565944 DOI: 10.1152/ajplung.00255.2003] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
G protein-coupled receptors (GPCRs) transduce extracellular signals into intracellular events. The waning responsiveness of GPCRs in the face of persistent agonist stimulation, or desensitization, is a necessary event that ensures physiological homeostasis. GPCR kinases (GRKs) are important regulators of GPCR desensitization. GRK5, one member of the GRK family, desensitizes central M(2) muscarinic receptors in mice. We questioned whether GRK5 might also be an important regulator of peripheral muscarinic receptor responsiveness in the cardiopulmonary system. Specifically, we wanted to determine the role of GRK5 in regulating muscarinic receptor-mediated control of airway smooth muscle tone or regulation of cholinergic-induced bradycardia. Tracheal pressure, heart rate, and tracheal smooth muscle tension were measured in mice having a targeted deletion of the GRK5 gene (GRK5(-/-)) and littermate wild-type (WT) control mice. Both in vivo and in vitro results showed that the airway contractile response to a muscarinic receptor agonist was not different between GRK5(-/-) and WT mice. However, the relaxation component of bilateral vagal stimulation and the airway smooth muscle relaxation resulting from beta(2)-adrenergic receptor activation were diminished in GRK5(-/-) mice. These data suggest that M(2) muscarinic receptor-mediated opposition of airway smooth muscle relaxation is regulated by GRK5 and is, therefore, excessive in GRK5(-/-) mice. In addition, this study shows that GRK5 regulates pulmonary responses in a tissue- and receptor-specific manner but does not regulate peripheral cardiac muscarinic receptors. GRK5 regulation of airway responses may have implications in obstructive airway diseases such as asthma or chronic obstructive pulmonary disease.
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Affiliation(s)
- J K L Walker
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA.
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12
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DeLorme MP, Yang H, Elbon-Copp C, Gao X, Barraclough-Mitchell H, Bassett DJP. Hyperresponsive airways correlate with lung tissue inflammatory cell changes in ozone-exposed rats. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2002; 65:1453-1470. [PMID: 12396876 DOI: 10.1080/00984100290071432] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The role of inflammatory cell infiltration in the development of hyperresponsiveness of the airways to muscarinic challenge remains poorly understood. Unlike previous investigations that only examined conducting airway inflammation, the present study utilized both bronchoalveolar lavage (BAL) and lung tissue digestion to determine rat lung inflammatory cell contents following a 4-h exposure to 2 ppm ozone. Immediately following ozone exposure, neutrophil content of the lung tissue was significantly increased and reached a value that was fourfold higher than air-exposed controls by 3 h postexposure. Although lavage-recovered neutrophils were elevated at 24 h, tissue neutrophil numbers had returned to control values. This transient elevation of tissue neutrophils directly correlated with an elevation and subsequent decline of airway hyperresponsiveness, measured as a decrease in the intravenous dose of methacholine provoking a 200% increase in airway resistance (PD(200)R). Animals rendered neutropenic with a rabbit anti-rat neutrophil serum prior to exposure were protected from ozone-induced hyperresponsive airways, further demonstrating an association between neutrophil infiltration into the lung and altered airway physiology. Although BAL-recovered neutrophils demonstrated no adverse effects as a result of ozone exposure, macrophages were not only found to be necrotic but also displayed altered oxidative metabolism when challenged with phorbol myristate acetate. Thus, changes in the microenvironment of the airways smooth muscle were shown to be associated with transient accumulation of neutrophils within the lung tissue and abnormalities of bronchoalveolar lavage-recovered macrophages.
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Affiliation(s)
- Michael P DeLorme
- Department of Occupational and Environmental Health Sciences, Wayne State University, Detroit, Michigan, USA.
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13
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Draghia-Akli R, Khan AS, Cummings KK, Parghi D, Carpenter RH, Brown PA. Electrical enhancement of formulated plasmid delivery in animals. Technol Cancer Res Treat 2002; 1:365-72. [PMID: 12625762 DOI: 10.1177/153303460200100507] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Electroporation has been shown to significantly increase plasmid transfer to the skeletal muscle, but this procedure is also implicated in muscle damage. We are reporting a highly efficient in vivo transfer of a plasmid formulated with poly-(L-glutamate) (PLG) into murine, canine and porcine muscle fibers using electric pulses of low field intensity. In mice and pigs, the use of secreted embryonic alkaline phosphatase (SEAP) as the indicator gene caused increased PLG expression by 2-3 fold compared to naked plasmid; while delivery of a PLG-plasmid formulation to dogs showed a 10-fold increase in serum SEAP levels compared to plasmid alone. Muscle lesions were reduced by the protective PLG. Thus, PLG may constitute a useful adjuvant for increased expression and reduced muscle trauma to plasmid DNA delivered by electroporation.
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Affiliation(s)
- Ruxandra Draghia-Akli
- Advisys, Inc., 2700 Research Forest Drive, Suite 180, The Woodlands, Texas 77381, USA.
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14
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Rodrigo GJ, Rodrigo C. The role of anticholinergics in acute asthma treatment: an evidence-based evaluation. Chest 2002; 121:1977-87. [PMID: 12065366 DOI: 10.1378/chest.121.6.1977] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The role for anticholinergic medications in acute asthma is not well-defined. Thus, the use of therapy with anticholinergics and beta(2)-agonists, either simultaneously or in sequence, has produced positive as well as negative results in trials. Therefore, the current recommendations for the use of these drugs in the emergency department (ED) and hospital management of asthma exacerbations are not precise. This review answers the following question: what level of evidence is available in the literature to support the use of anticholinergic medications in combination with beta(2)-agonists in acute asthma patients? We limited the search on our therapy question to systematic reviews of randomized trials and/or randomized controlled trials not included in the reviews. After an extensive review of the most relevant evidence, the following conclusions may be emphasized. (1) The use of multiple doses of ipratropium bromide are indicated in the ED treatment of children and adults with severe acute asthma. The studies reported a substantial reduction in hospital admissions (30 to 60%; number needed to treat, 5 to 11) and significant differences in lung function favoring the combined treatment. No apparent increase in the occurrence of side effects was observed. (2) The use of single-dose protocols of ipratropium bromide with beta(2)-agonist treatment produced, particularly in children with more severe acute asthma, a modest improvement in pulmonary function without reduction in hospital admissions; in adults, the data showed a similar increase in pulmonary function with an approximately 35% reduction in the hospital admission rate. In patients with mild-to-moderate acute asthma, there is no apparent benefit from adding a single dose of an anticholinergic medication.
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Affiliation(s)
- Gustavo J Rodrigo
- Departamento de Emergencia, Hospital Central de las Fuerzas Armadas, Montevideo, Uruguay.
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15
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Avraham Y, Hao S, Mendelson S, Bonne O, Berry EM. Diet restriction in mice causes a decrease in hippocampal choline uptake and muscarinic receptors that is restored by administration of tyrosine: interaction between cholinergic and adrenergic receptors influencing cognitive function. Nutr Neurosci 2002; 4:153-67. [PMID: 11842883 DOI: 10.1080/1028415x.2001.11747359] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
We have studied the effects of diet restriction (DR) to 60% and 40% of daily requirements, and tyrosine administration on cognitive function in mice, to define the nutritional-neurochemical interactions on autonomic tone involved in behavior and energy regulation. Cognitive function in the Morris Water maze was significantly impaired after 40% DR compared to both control and 60% DR. It was restored after tyrosine in association with increased M1 cholinergic and beta-adrenergic receptor function, and decreased alpha-adrenergic function. DR to 40% significantly decreased choline uptake (p <.05) and M1 receptor number (Bmax) (p <.05), without changes in affinity (Kd), choline acetyl transferase (ChAT) or acetyl cholinesterase (AChE) activity. Tyrosine administration significantly increased choline uptake (Bmax) (p <.05) and M1 density in the 40% DR (p <.01) without changes in affinity. ChAT activity was decreased after tyrosine--significantly after 40% DR (p <.05) while AChE was not affected. Both M1 mRNA and protein were not influenced by DR or tyrosine administration. Tyrosine hydroxylase mRNA was decreased significantly by 40% DR (p <.01). The effect of DR and tyrosine appeared to be both pre- and post-synaptic, indicating modulation of cholinergic activity by adrenergic tone. Nutritional effect on behavior and autonomic tone may have implications for the treatment of mood changes associated with weight loss and semi-starvation.
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Affiliation(s)
- Y Avraham
- Department of Human Nutrition and Metabolism, Hebrew University, Hadassah Medical School, Jerusalem, Israel
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16
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Yahata T, Nishimura Y, Maeda H, Yokoyama M. Modulation of airway responsiveness by anionic and cationic polyelectrolyte substances. Eur J Pharmacol 2002; 434:71-9. [PMID: 11755168 DOI: 10.1016/s0014-2999(01)01528-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
To elucidate the effects of anionic and cationic polyelectrolyte substance on bronchoconstriction, we examined the serial changes in respiratory resistance (Rrs) in ovalbumin-sensitized guinea pigs after antigen exposure with or without pre-inhalation of low-molecular-weight heparin, poly-L-glutamic acid, poly-L-lysine and dextran, and with or without oral intake of dalteparin. Both immediate and late responses after antigen exposure were significantly decreased after pretreatment with inhaled low-molecular-weight heparin and poly-L-glutamic acid compared with saline alone. The late response was significantly decreased after pretreatment with oral dalteparin. Both low-molecular-weight heparin and poly-L-glutamic acid significantly decreased the airway response to methacholine in sensitized guinea pigs. In sensitized guinea pigs, the airway response to methacholine was significantly increased after pretreatment with inhaled poly-L-lysine. Pretreatment with inhaled low-molecular-weight heparin before poly-L-lysine exposure significantly suppressed the airway hyperresponsiveness after inhaled poly-L-lysine. These findings indicated that the "cationic-anionic interaction" plays an important role in airway responsiveness.
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Affiliation(s)
- Tomoyuki Yahata
- Division of Cardiovascular and Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan
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17
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Fenech AG, Ebejer MJ, Felice AE, Ellul-Micallef R, Hall IP. Mutation screening of the muscarinic M(2) and M(3) receptor genes in normal and asthmatic subjects. Br J Pharmacol 2001; 133:43-8. [PMID: 11325793 PMCID: PMC1572756 DOI: 10.1038/sj.bjp.0704039] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. Muscarinic receptors are important in the development of airway hyperresponsiveness, and dysfunction of these receptors has been suggested to be present in asthma. 2. The human muscarinic M(2) and M(3) receptor genes were screened for polymorphic variation using single-stranded conformation polymorphism (SSCP) analysis, complemented by direct fluorescent sequencing. Forty-six random DNA samples and 46 respiratory physician diagnosed asthmatic samples were used as a template for analysis. 3. Within the muscarinic M(2) receptor gene, we identified two degenerate single base substitutions (1197T-->C, Thr-->Thr and 976A-->C, Arg-->Arg) in one random and one asthmatic sample respectively. Analysis of the 3' UTR region revealed an additional 'A' at bp 1793 (c.f. ATG). This was present in all of 49 samples analysed by sequencing or BsmI digest, suggesting that the published sequence (GenBank Accession NO: M16404) is incorrect. A common 3' UTR polymorphism (T-->A) was found at bp 1696 (c.f. ATG) (allelic frequency=65%, n=60), but this does not alter transcription factor recognition sites. 4. We were unable to identify any polymorphic variation within the muscarinic M(3) coding region or the flanking regions investigated, using the methods described. 5. The coding regions for the human muscarinic M(2) and M(3) receptor genes are both highly conserved. These data suggest that polymorphic variation within these coding sequences is unlikely to account for inter-individual variability in response to methacholine or anticholinergic therapy. The potential functional significance of the muscarinic M(2) receptor 3' UTR polymorphism (bp 1696) remains to be determined.
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Affiliation(s)
- A G Fenech
- Department of Clinical Pharmacology and Therapeutics, University of Malta, Msida MSD 06, Malta
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18
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Scichilone N, Permutt S, Togias A. The lack of the bronchoprotective and not the bronchodilatory ability of deep inspiration is associated with airway hyperresponsiveness. Am J Respir Crit Care Med 2001; 163:413-9. [PMID: 11179115 DOI: 10.1164/ajrccm.163.2.2003119] [Citation(s) in RCA: 131] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
In healthy subjects, deep inspiration (DI) acts both as a bronchodilator and a bronchoprotector. The latter is impaired in asthmatics. We have now evaluated whether the lack of bronchoprotection is related to bronchial hyperresponsiveness (BHR), and whether the bronchodilatory effect is also lost in asthmatics. Ten healthy subjects (PC20 > 75 mg/ml), 12 asthmatics with moderate to severe BHR (PC20 < 1 mg/ml), 14 asthmatics with mild to borderline BHR (1 < PC20 < 25 mg/ml), and 10 rhinitics with mild to borderline BHR (1 < PC20 < 25 mg/ml) underwent single-dose methacholine provocations inducing at least 20% reduction in FEV1 after 20 min of DI inhibition. To measure the bronchodilatory effect, DIs were taken immediately after the postmethacholine spirometry, and lung function was again tested. To measure the bronchoprotective effect, DIs were taken before the administration of spasmogen. All four groups achieved the same reductions in FEV1 and FVC, in the absence of deep breaths (analysis of variance [ANOVA], p = 0.49). Only healthy subjects showed bronchoprotection (percent bronchoprotection, mean +/- SEM; healthy: 79 +/- 4.0; asthmatics with moderate to severe BHR: 12 +/- 14.5; asthmatics with mild to borderline BHR: -7 +/- 19.7; rhinitics with mild to borderline BHR: 2 +/- 14.0). In contrast, DIs were able to partially reverse bronchial obstruction in all four groups, albeit percent bronchodilation in healthy subjects was somewhat stronger. The dissociation between bronchoprotection and bronchodilation suggests that the two effects involve different mechanisms.
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Affiliation(s)
- N Scichilone
- Division of Clinical Immunology, Department of Medicine, Johns Hopkins University, School of Medicine, Baltimore, Maryland, USA.
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19
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Golkar L, Yarkony KA, Fryer AD. Inhibition of neuronal M(2) muscarinic receptor function in the lungs by extracellular nitric oxide. Br J Pharmacol 2000; 131:312-8. [PMID: 10991925 PMCID: PMC1572309 DOI: 10.1038/sj.bjp.0703542] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/1999] [Revised: 05/29/2000] [Accepted: 06/16/2000] [Indexed: 11/08/2022] Open
Abstract
1. These experiments were carried out to test whether neuronal M(2) muscarinic receptor function in the lungs is affected by nitric oxide (NO) and whether the source of the NO is epithelial or neuronal. 2. In pathogen free, anaesthetized guinea-pigs, the muscarinic agonist pilocarpine inhibited vagally induced bronchoconstriction demonstrating functional neuronal M(2) muscarinic receptors. In the presence of the NO donor, 3-morpholino-sydnonimine (SIN-1), pilocarpine no longer inhibited vagally induced bronchoconstriction. In contrast, inhibiting endogenous NO with N(G)-monomethyl-L-arginine methyl ester (L-NMMA) did not affect the ability of pilocarpine to decrease vagally induced bronchoconstriction. 3. In isolated tracheas, pilocarpine inhibited contractions induced by electrical field stimulation demonstrating that neuronal M(2) muscarinic receptors function in vitro. As in the anaesthetized guinea-pigs, SIN-1 shifted the pilocarpine dose response curve to the right, demonstrating decreased neuronal M(2) receptor function. However, in vitro, L-NMMA shifted the pilocarpine dose response curve to the left, demonstrating that endogenous NO was inhibiting the ability of the M(2) receptors to decrease acetylcholine (ACh) release. 4. Both haemoglobin (Hb), which scavenges NO, and epithelial removal also shifted the pilocarpine dose response curve to the left, demonstrating that the NO inhibiting neuronal M(2) receptor function was extracellular and probably of epithelial origin. 5. In conclusion, extracellular NO appears to inhibit the ability of the M(2) receptors to decrease ACh release from the parasympathetic nerves in the lungs in vivo and in vitro in pathogen free guinea-pigs. However, while the neuronal M(2) receptors will respond to NO (from SIN-1) in vivo, there does not appear to be an endogenous source of NO since L-NMMA had no effect in vivo.
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Affiliation(s)
- Laleh Golkar
- Johns Hopkins University School of Public Health, 615 N Wolfe Street, Baltimore, Maryland, MD 21209, U.S.A
| | - Kathryn A Yarkony
- Johns Hopkins University School of Public Health, 615 N Wolfe Street, Baltimore, Maryland, MD 21209, U.S.A
| | - Allison D Fryer
- Johns Hopkins University School of Public Health, 615 N Wolfe Street, Baltimore, Maryland, MD 21209, U.S.A
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20
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Abstract
Acute asthma exacerbations are common. Patients with asthma experience symptoms in response to a wide variety of stimuli, and identifying the precipitating cause may be useful in guiding treatment and preventing future attacks. A case of asthma exacerbation occurring during multiple defecations is reported. Abnormal parasympathetic tone has been implicated in the pathogenesis of certain types of asthma, and defecation can be associated with increased parasympathetic tone. This patient's pattern of defecation-related asthma exacerbations responded to prophylactic anticholinergic medication.
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Affiliation(s)
- L Rossman
- Department of Emergency Medicine, Alameda County Medical Center, Oakland, California 94602, USA
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21
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van der Velden VH, Hulsmann AR. Autonomic innervation of human airways: structure, function, and pathophysiology in asthma. Neuroimmunomodulation 1999; 6:145-59. [PMID: 10213912 DOI: 10.1159/000026376] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The human airways are innervated via efferent and afferent autonomic nerves, which regulate many aspects of airway function. It has been suggested that neural control of the airways may be abnormal in asthmatic patients, and that neurogenic mechanisms may contribute to the pathogenesis and pathophysiology of asthma. In this review, the autonomic innervation of the human airways and possible abnormalities in asthma are discussed. The parasympathetic nervous system is the dominant neuronal pathway in the control of airway smooth muscle tone. Stimulation of cholinergic nerves causes bronchoconstriction, mucus secretion, and bronchial vasodilation. Although abnormalities of the cholinergic innervation have been suggested in asthma, thus far the evidence for cholinergic dysfunction in asthmatic subjects is not convincing. Sympathetic nerves may control tracheobronchial blood vessels, but no innervation of human airway smooth muscle has been demonstrated. beta-Adrenergic receptors, however, are abundantly expressed on human airway smooth muscle and activation of these receptors causes bronchodilation. The physiological role of beta-adrenergic receptors is unclear and their function seems normal in asthmatic patients. Inhibitory nonadrenergic noncholinergic (NANC) nerves, containing vasoactive intestinal peptide and nitric oxide, may be the only neural bronchodilator pathways in human airways. Although a dysfunction of inhibitory NANC nerves has been proposed in asthma, thus far no differences in inhibitory NANC responses have been found between asthmatics and healthy subjects. Excitatory NANC nerves, extensively studied in animal airways, have also been detected in human airways. In animal studies, stimulation of excitatory NANC nerves causes bronchoconstriction, mucus secretion, vascular hyperpermeability, cough, and vasodilation, a process called 'neurogenic inflammation'. Recent studies have demonstrated an interaction between the excitatory NANC nervous system and inflammatory cells. Neuropeptides may influence the recruitment, proliferation, and activation of leukocytes. On the other hand, inflammatory cells may modulate the neuronal phenotype and function. The functional relevance of the excitatory NANC nervous system and its interaction with the immune system in asthma still remains to be elucidated.
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Affiliation(s)
- V H van der Velden
- Department of Immunology, Erasmus University and University Hospital Dijkzigt, Rotterdam, The Netherlands.
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22
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Barnes PJ, Belvisi MG, Mak JC, Haddad EB, O'Connor B. Tiotropium bromide (Ba 679 BR), a novel long-acting muscarinic antagonist for the treatment of obstructive airways disease. Life Sci 1999; 56:853-9. [PMID: 10188785 DOI: 10.1016/0024-3205(95)00020-7] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Tiotropium bromide (Ba 679 BR) is a novel potent and long-lasting muscarinic antagonist that has been developed for the treatment of chronic obstructive airways disease (COPD). Binding studies with [3H]tiotropium bromide in human lung have confirmed that this is a potent muscarinic antagonist with equal affinity for M1-, M2- and M3-receptors and is approximately 10-fold more potent than ipratropium bromide. Tiotropium bromide dissociates very slowly from lung muscarinic receptors compared with ipratropium bromide. In vitro tiotropium bromide has a potent inhibitory effect against cholinergic nerve-induced contraction of guinea-pig and human airways, that has a slower onset than atropine or ipratropium bromide. After washout, however, tiotropium bromide dissociates extremely slowly compared with the dissociation of atropine and ipratropium bromide. Measurement of acetylcholine (ACh) release from guinea-pig trachea shows that tiotropium bromide, ipratropium bromide and atropine all increase ACh release on neural stimulation and that this effect is washed out equally quickly for the three antagonists. This confirms binding studies to transfected human muscarinic receptors which suggested that tiotropium bromide dissociates slowly from M3-receptors (on airway smooth muscle) but rapidly from M2 autoreceptors (on cholinergic nerve terminals). Clinical studies with inhaled tiotropium bromide confirm that it is a potent and long-lasting bronchodilator in COPD and asthma. Furthermore, it protects against cholinergic bronchoconstriction for > 24 h. This suggests that tiotropium bromide will be a useful bronchodilator, particularly in patients with COPD, and may be suitable for daily dosing. The selectivity for M3- over M2-receptors may also confer a clinical advantage.
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Affiliation(s)
- P J Barnes
- Department of Thoracic Medicine, National Heart and Lung Institute, London, UK
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23
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Walker JK, Peppel K, Lefkowitz RJ, Caron MG, Fisher JT. Altered airway and cardiac responses in mice lacking G protein-coupled receptor kinase 3. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 276:R1214-21. [PMID: 10198406 DOI: 10.1152/ajpregu.1999.276.4.r1214] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Contraction and relaxation of airway smooth muscles is mediated, in part, by G protein-coupled receptors (GPCRs) and dysfunction of these receptors has been implicated in asthma. Phosphorylation of GPCRs, by G protein-coupled receptor kinase (GRK), is an important mechanism involved in the dampening of GPCR signaling. To determine whether this mechanism might play a role in airway smooth muscle physiology, we examined the airway pressure time index and heart rate (HR) responses to intravenous administration of the cholinergic agonist methacholine (MCh) in genetically altered mice lacking one copy of GRK2 (GRK2 +/-), homozygous GRK3 knockout (GRK3 -/-), and wild-type littermates. (GRK2 -/- mice die in utero.) GRK3 -/- mice demonstrated a significant enhancement in the airway response to 100 and 250 microgram/kg doses of MCh compared with wild-type and GRK2 +/- mice. GRK3 -/- mice also displayed an enhanced sensitivity of the airway smooth muscle response to MCh. In addition, GRK3 -/- mice displayed an altered HR recovery from MCh-induced bradycardia. Although direct stimulation of cardiac muscarinic receptors measured as vagal stimulation-induced bradycardia was similar in GRK3 -/- and wild-type mice, the baroreflex increase in HR associated with sodium nitroprusside-induced hypotension was significantly greater in GRK3 -/- than wild-type mice. Therefore, these data demonstrate that in the mouse, GRK3 may be involved in modulating the cholinergic response of airway smooth muscle and in regulating the chronotropic component of the baroreceptor reflex.
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Affiliation(s)
- J K Walker
- Howard Hughes Medical Institute, Department of Cell Biology, Duke University Medical Center, Durham, North Carolina 27710, USA
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24
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Abstract
Since the cloning and expression of many of the G protein-coupled receptors during the 1980s, there has been a massive increase in our understanding of many aspects of their function. The use of molecular biology to engineer and express mutant receptors has made it possible to determine key amino acids involved in receptor function. Although advances in molecular biology have contributed greatly to our understanding of the pharmacology and structure of the five subtypes of muscarinic receptor, much remains to be learned about the factors that regulate their expression and function. This review by El-Bdaoui Haddad and Jonathan Rousell describes the current state of awareness and highlights recent advances made in the elucidation of the mechanisms involved in muscarinic receptor regulation. Because most is known about the regulation of expression of the M2 receptor subtype, particular attention will be paid to it. Furthermore, this receptor subtype plays an important role in regulating acetylcholine output from airway cholinergic nerves, and there is substantial evidence from studies both in vivo and in vitro in human and animal models that these receptors are dysfunctional in asthma.
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25
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Costello RW, Jacoby DB, Fryer AD. Pulmonary neuronal M2 muscarinic receptor function in asthma and animal models of hyperreactivity. Thorax 1998; 53:613-6. [PMID: 9797763 PMCID: PMC1745261 DOI: 10.1136/thx.53.7.613] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
In the lungs neuronal M2 muscarinic receptors limit acetylcholine release from postganglionic cholinergic nerves. These inhibitory M2 receptors are dysfunctional in antigen challenged guinea pigs and in humans with asthma which leads to an increase in vagally mediated hyperreactivity. In vitro, eosinophil products act as allosteric antagonists at neuronal M2 muscarinic receptors. In vivo, displacing or neutralising MBP preserves neuronal M2 muscarinic receptor function and prevents hyperreactivity. Thus, there is good evidence from animal studies that after antigen challenge pulmonary M2 muscarinic receptors become dysfunctional because MBP inhibits their function. Loss of function of pulmonary neuronal M2 muscarinic receptors has also been reported in patients with asthma, although the clinical significance of this dysfunction and the mechanisms underlying it are not yet established.
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Affiliation(s)
- R W Costello
- Department of Medicine, University of Liverpool, UK
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26
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Abstract
Muscarinic M1, M2, and M3 receptor subtypes have been shown to be involved in the pre- and postjunctional control of airway diameter of various species, including man. In a guinea pig model of allergic asthma, the prejunctional M2 receptor was shown to become dysfunctional already during the early allergic reaction, thereby contributing to exaggerated vagal reflex activity and airway hyperreactivity. Moreover, a deficiency of endogenous nitric oxide was observed after allergen provocation, which may also contribute to an enhanced postjunctional M3 receptor-mediated cholinergic response. Both in human and in animal airway preparations it was shown that enhanced cholinergic contractions are relatively resistent to beta-adrenoceptor-mediated relaxation. The reduced beta-adrenoceptor function may primarily be due to transductional cross-talk between PI metabolism and adenylyl cyclase, including protein kinase C-induced uncoupling of the beta-adrenoceptor from the effector system. Cross-talk between postjunctional M2 receptor-mediated inhibition and beta-adrenoceptor-induced activation of adenylyl cyclase appears to be of minor functional importance, but could be enhanced in allergic asthma due to increased expression of the inhibitory G protein as induced by cytokines.
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Affiliation(s)
- J Zaagsma
- Department of Molecular Pharmacology, University Centre for Pharmacy, Groningen, The Netherlands
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27
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Abstract
The molecular mechanisms involved in the regulation of muscarinic receptor gene expression are poorly understood. In an effort to gain a better understanding of the regulation of M2 receptors, we have investigated homologous and heterologous regulation of M2 muscarinic receptor protein and gene expression in human embryonic lung fibroblasts (HEL 299 cells). HEL 299 cells constitutively express m2 receptors, with no evidence of other muscarinic receptor subtypes. We have shown that M2 receptors in these cells can be down-regulated by muscarinic and beta2-adrenergic receptor agonists. Unlike the down-regulation mediated by muscarinic and beta-adrenergic stimulation, activation of PKC with PDBu was mediated through changes in m2 muscarinic receptor mRNA through reduced gene transcription. Because of the inflammatory nature of asthma, we have focused on delineating the interactions between cytokines and M2 receptors in an attempt to define potential endogenous modulators of M2 receptor expression. We have shown that the multi-functional cytokine, transforming growth factor beta1 (TGF-beta1), which is involved in several inflammatory conditions induces desensitization and down-regulation of M2 muscarinic receptor protein and gene expression that was mediated through a reduction in the rate of m2 receptor gene transcription. Other cytokines of interest are tumor necrosis factor alpha (TNF-alpha) and interleukin 1beta (IL-1beta) which are elevated in asthma. We have demonstrated that TNF-alpha and IL-1beta synergise to induce down-regulation of M2 muscarinic receptor protein and mRNA which was associated with functional desensitization of the receptor protein. The M2 receptor mRNA down-regulation appeared to be mediated through a reduction in the rate of m2 receptor gene transcription which may be dependent on the transcription and translation of unknown protein factor(s). Moreover, a role of PKA and ceramide pathways in M2 receptor regulation is suggested. Collectively, our work provides a mechanistic explanation of previous reports indicating altered function of M2 receptors in asthma. Ours results also suggest that the expression of this receptor subtype may be under the control of a cytokine network at the airways.
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Affiliation(s)
- P J Barnes
- Department of Thoracic Medicine, Imperial College School of Medicine at National Heart and Lung Institute, London, UK
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28
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Abstract
The treatment of airway obstructive disease may be improved by antimuscarinic agents which selectively block M1 and M3 receptors but do not inhibit prejunctional cholinergic autoreceptors which limit release of acetylcholine. Revatropate is a novel antimuscarinic agent which shows some 50-fold selectivity for M1 and M3 receptors in guinea pig trachea and rabbit vas deferens over the M2 subtype in atria. This selectivity profile was seen in vivo in anaesthetised guinea pigs and conscious dogs where bronchodilator activity was produced in the absence of any effect on heart rate. Revatropate, in contrast to the non-selective agent ipratropium, did not potentiate bronchoconstrictor responses induced by vagal nerve stimulation, indicating that inhibitory autoreceptors were still functional. Early clinical studies in COAD patients showed that inhaled revatropate was an effective bronchodilator which was well tolerated. Darifenacin differs from revatropate by showing selectivity for M3 receptors relative to both M2 and M1 subtypes. [3H] darifenacin had 5-fold higher affinity for the human m3 relative to m1 receptors while there was significantly reduced binding to m2, m4 and m5 receptors. The degree of selectivity in functional tissue preparations was even greater, with darifenacin showing 100-fold selectivity for the ileum M3 receptors over M2 receptors in atria and 30-fold over M1 receptors in rabbit vas deferens. Darifenacin was able to differentiate between M3 receptors in different tissues; although darifenacin was equipotent with atropine in the ileum and bladder, it was some 10-fold and 6-fold less potent at inhibiting muscarinic responses in the trachea and submandibular salivary gland respectively, relative to atropine. Studies in anaesthetised dogs confirmed this selectivity profile. Thus darifenacin inhibited responses of the gut and bladder to cholinergic stimulation without affecting heart rate. Salivary gland responses were inhibited at doses some 6-10 fold higher than those required to inhibit gut and bladder responses. Clinical studies are ongoing in urge incontinence and functional bowel disease which may confirm this selectivity profile.
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Affiliation(s)
- V A Alabaster
- Department of Discovery Biology, Pfizer Central Research, Sandwich, Kent, U.K
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Ten Berge RE, Krikke M, Teisman AC, Roffel AF, Zaagsma J. Dysfunctional muscarinic M2 autoreceptors in vagally induced bronchoconstriction of conscious guinea pigs after the early allergic reaction. Eur J Pharmacol 1996; 318:131-9. [PMID: 9007524 DOI: 10.1016/s0014-2999(96)00820-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We studied the function of autoinhibitory muscarinic M2 receptors on vagal nerve endings in the airways of conscious, unrestrained, ovalbumin-sensitized guinea pigs after the early and late allergic reaction. For this purpose, the effects of the selective muscarinic M2 receptor antagonist gallamine were examined on unilateral vagus nerve stimulation-induced bronchoconstriction, which was determined as an increase in basal respiration amplitude, measured as changes in pleural pressure. Under control conditions, i.e., before antigen challenge, a significant increase in the pleural pressure was found after inhalation of 0.1 mM and, even more pronounced, 1.0 mM gallamine, at medium stimulation frequencies (2-16 Hz), leading to a leftward shift of the frequency-response curve. After inhalation of 10 mM of gallamine, a complete reversal of the left-shift was observed and the frequency-response curve was depressed. However, 6 h after challenge with ovalbumin (i.e., after the early allergic reaction) no increase in nerve stimulation-induced bronchoconstriction by gallamine was found; a decrease in this bronchoconstriction was again observed with the highest concentration. At this moment, bronchial responsiveness to histamine was enhanced 4.5-fold compared to control, i.e., prior to antigen provocation. Both after the late allergic response (24 h after challenge; 1.6-fold histamine hyperresponsiveness) and 4 days after allergen challenge (normal histamine responsiveness) the gallamine-induced potentiation of the bronchoconstriction was restored, similar to the responses under control conditions. The results clearly demonstrate that prejunctional muscarinic M2 receptors control bronchoconstriction in conscious, unrestrained guinea pigs in vivo. Furthermore, these autoinhibitory receptors appear to be completely dysfunctional after the early allergic phase, but their function is largely restored after the late phase. The results indicate that dysfunction of autoinhibitory muscarinic M2 receptors might contribute to the strongly enhanced responsiveness to histamine after the early allergic response.
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Affiliation(s)
- R E Ten Berge
- Department of Molecular Pharmacology, University Centre for Pharmacy, University of Groningen, Netherlands
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30
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Haddad EB, Rousell J, Lindsay MA, Barnes PJ. Synergy between tumor necrosis factor alpha and interleukin 1beta in inducing transcriptional down-regulation of muscarinic M2 receptor gene expression. Involvement of protein kinase A and ceramide pathways. J Biol Chem 1996; 271:32586-92. [PMID: 8955085 DOI: 10.1074/jbc.271.51.32586] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Stimulation of HEL 299 cells with tumor necrosis factor alpha (TNF-alpha) or interleukin 1beta (IL-1beta) had no effect on M2 muscarinic receptor expression. However, the combination of these two cytokines markedly down-regulated muscarinic M2 receptor protein and mRNA expression and uncoupled M2 receptors from adenylyl cyclase. There was no effect of TNF-alpha and IL-1beta on the m2 muscarinic receptor mRNA stability, and nuclear run-on assays showed reduced m2 receptor gene transcription. Sequential cytokine addition suggests that the synergy involves postreceptor events. Although the cAMP-dependent protein kinase inhibitor H8 provided a significant protection against receptor down-regulation, the protein kinase C inhibitor GF109203X had no effect. The ceramide analog C2-ceramide (N-acetylsphingosine) was without effect on m2 receptor expression. However, a strong synergistic effect was demonstrated when cells were treated with the combination of C2-ceramide and TNF-alpha or IL-1beta. TNF-alpha and/or IL-1beta combination also activated the 46- and 55-kDa c-Jun NH2-terminal protein kinases and to a lesser extent p42 and p44 mitogen-activated protein kinase isoforms. Cycloheximide abolished the TNF-alpha and IL-1beta effect, suggesting that de novo protein synthesis is required for receptor down-regulation. These results suggest that the TNF-alpha and IL-1beta synergize to induce transcriptional down-regulation of the M2 muscarinic receptor, which seems to be mediated through activation of both ceramide and cAMP-dependent protein kinase pathways. Furthermore, these results suggest that M2 receptor expression is under the control of a cytokine network.
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Affiliation(s)
- E B Haddad
- Department of Thoracic Medicine, National Heart and Lung Institute, Imperial College of Science, Technology, and Medicine, Dovehouse Street, London SW3 6LY, United Kingdom.
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Kahn RM, Okanlami OA, Jacoby DB, Fryer AD. Viral infection induces dependence of neuronal M2 muscarinic receptors on cyclooxygenase in guinea pig lung. J Clin Invest 1996; 98:299-307. [PMID: 8755638 PMCID: PMC507431 DOI: 10.1172/jci118793] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Inhibitory M2 muscarinic receptors on parasympathetic nerve endings in the lungs decrease release of acetylcholine, inhibiting vagally induced bronchoconstriction. Neuronal M2 receptor function can be studied using selective agonists and antagonists such as pilocarpine and gallamine. In pathogen-free guinea pigs indomethacin (1 mg/kg) did not alter the effect of either gallamine or pilocarpine, thus in pathogen free animals neuronal M2 muscarinic receptors function independently of cyclooxygenase products. However, in guinea pigs infected with virus, (which causes temporary loss of M2 receptor function), and then allowed to recover for 8 wk (to allow recovery of M2 receptors), indomethacin prevented both gallamine's potentiation and pilocarpine's inhibition of vagally induced bronchoconstriction. This new effect of indomethacin was not blocked by the addition of a 5-lipoxygenase inhibitor, AA861. However, the selective COX II inhibitor, L-745,337, had the same effect as indomethacin. Since exposure to ozone also caused neuronal M2 receptors to become dependent upon cyclooxygenase the effects of viral infection are likely to be due to inflammation. Thus, despite apparent recovery of normal M2 receptor function after viral infection or ozone, linkage of these receptors is chronically altered such that they become largely dependent on the activity of COX II.
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Affiliation(s)
- R M Kahn
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University, Baltimore, Maryland 21205, USA
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ten Berge RE, Santing RE, Hamstra JJ, Roffel AF, Zaagsma J. Dysfunction of muscarinic M2 receptors after the early allergic reaction: possible contribution to bronchial hyperresponsiveness in allergic guinea-pigs. Br J Pharmacol 1995; 114:881-7. [PMID: 7773550 PMCID: PMC1510216 DOI: 10.1111/j.1476-5381.1995.tb13286.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
1. Using a guinea-pig model of allergic asthma, in which the animals display early (0-5 h) and late phase (8-23 h after antigen challenge) bronchoconstrictor reactions, the function of prejunctional inhibitory M2 and postjunctional M3 receptors in isolated tracheal preparations have been investigated. In addition, cardiac M2 receptor function in vitro and bronchial responsiveness to histamine in vivo were evaluated. 2. Sensitivity to inhaled histamine was increased 3.1 fold and 1.6 fold after the early and late allergic reactions (i.e. at 5 h and 23 h after a single ovalbumin challenge), respectively. At 23 h after the last of four allergen challenges, executed on four consecutive days, bronchial hyperresponsiveness to histamine was diminished to 1.3 fold. 3. After the early response, there was no change in cardiac muscarinic M2 receptor function, since in left atria pD2 (-log EC50) and Emax values of pilocarpine and pKB values of AQ-RA 741, a selective M2 receptor antagonist, were not significantly different from controls (unchallenged sensitized animals), and this also applied to methacholine pD2 values for muscarinic M3 receptors in tracheal smooth muscle. 4. Prejunctional inhibitory muscarinic M2 autoreceptors in airway smooth muscle were markedly dysfunctional after the early allergic response, since potentiation of electrically evoked twitch contractions of tracheal preparations by low concentrations of the M2-selective muscarinic receptor antagonists, gallamine, methoctramine, AQ-RA 741 and AF-DX 116, which is the result of M2 receptor blockade, was clearly and significantly diminished compared to controls. However, after the late response, both in single and repeatedly challenged animals, twitch potentiation was not significantly different from and similar to controls, indicating restoration of M2 receptor function during the late allergic reaction.5. It is concluded that dysfunction of muscarinic M2 autoreceptors in the airways of sensitized and challenged guinea-pigs is already present after the early allergic reaction, and that it has recovered after the late response. Since histamine-induced bronchoconstriction involves vagal pathways, the present results suggest that bronchial hyperresponsiveness to histamine is partly due to M2 auto receptor dysfunction, leading to increased release of acetylcholine.
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Affiliation(s)
- R E ten Berge
- Department of Medicinal Chemistry and Molecular Pharmacology, University Centre for Pharmacy, Groningen, The Netherlands
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Henry PJ, Goldie RG. ETB but not ETA receptor-mediated contractions to endothelin-1 attenuated by respiratory tract viral infection in mouse airways. Br J Pharmacol 1994; 112:1188-94. [PMID: 7952880 PMCID: PMC1910230 DOI: 10.1111/j.1476-5381.1994.tb13209.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
1. The current study investigated the effects of respiratory tract viral infection on the density of ETA and ETB receptors in murine tracheal smooth muscle and on the contractile response to endothelin-1 mediated by these receptors. 2. Quantitative autoradiographic studies using [125I]-endothelin-1 revealed that tracheal smooth muscle from control mice contained ETA and ETB receptors in the ratio of 42%:58% (+/- 4%, n = 10 mice), respectively. In contrast, tracheal smooth muscle obtained from mice 2 days post-inoculation with Influenza A/PR-8/34 virus contained 23 +/- 2% fewer receptors for [125I]-endothelin-1 (n = 10, P < 0.01). This reflected a selective reduction in ETB receptor density and a change in the ratio of ETA and ETB receptors to 77%:23% (+/- 5%, n = 10 mice), respectively. 3. The ETB receptor-selective agonist, sarafotoxin S6c, was a potent spasmogen of murine isolated tracheal smooth muscle and the EC50 for contraction was similar in preparations from control (3.6 nM [95% confidence limits, 2.7-4.8 nM], n = 16 preparations from 8 mice) and virus-inoculated mice (3.0 nM [2.4-3.7 nM], n = 16 preparations from 8 mice). However, the maximum contractions induced by sarafotoxin S6c (100 nM) in the preparations from virus-inoculated mice (37 +/- 5% Cmax, where 100% Cmax was the response to 10 microM carbachol) were significantly smaller than those from control mice (85 +/- 4% Cmax, P < 0.01). 4. Contractions induced by endothelin-1 in tracheal smooth muscle preparations obtained from virus inoculated mice (EC50 for contraction, 6.5 nM [95% confidence limits, 2.7-16 nM]; maximum contraction,112 +/- 5% Cm.; n = 4) were similar to those induced by endothelin-1 in control preparations (ECm9.3 nM (4.2-21); maximum contraction, 110 +/- 3% Cmax; n = 4). Endothelin-1-induced contractions in control preparations were only marginally inhibited by the ETA receptor-selective antagonist BQ-123 (in the presence of 3 micro M BQ-123; EC50 for contraction, 5.9 nM [4.1-8.5]; maximum contraction, 82 +/- 4%Cmax; n = 4). In contrast, 3 microM BQ-123 caused a 50 fold rightward shift (17-160, n =4) of the concentration-effect curve to endothlin-1 in preparations obtained from virus-inoculated mice (measured at the 30% Cmax level of contraction).5. Tracheal smooth muscle preparations exposed to 100 nM sarafotoxin S6c for 30 min (followed by a 30 min washout period) did not contract to subsequently administered sarafotoxin S6c (1-100 nM;n = 8), but contracted normally in response to endothelin-1 (EC50 6.5 nM (2.3-18); maximum contraction,109 +/- 2% Cmax; n = 4). Endothelin-l-induced contractions in these ETB receptor desensitized preparations were markedly inhibited by 3 microM BQ-123, irrespective of whether the preparations were obtained from control (63 fold shift (10-400) at the 30% Cma. level of contraction, n = 4) or virus inoculated mice (46 fold shift (18-120), n = 4).6. In summary, tracheal smooth muscle obtained from mice infected with a respiratory tract virus,Influenza A/PR-8/34 had a reduced density of ETB receptors and an attenuated ETB receptor-mediated contractile response to sarafotoxin S6c and endothelin-1. Virus-inoculation was also associated with a modest increase in tracheal smooth muscle ETA receptor density, although no significant change in ETA receptor-mediated contractile activity was seen. Thus, virus infection in murine airways produced profound alterations in endothelin receptor density, some of which were associated with changes in receptor-mediated contractile activity.
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Affiliation(s)
- P J Henry
- Department of Pharmacology, University of Western Australia, Nedlands
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