Asthma diagnosis and treatmentEvidence of remodeling in peripheral airways of patients with mild to moderate asthma: Effect of hydrofluoroalkane-flunisolide
Section snippets
Study design
A single-center, open-label study was conducted in adult patients with asthma to evaluate the effect of inhaled small-particle corticosteroids (HFA-flunisolide) on peripheral lung inflammation and remodeling. The study was performed in full compliance with Food and Drug Administration Guidelines for Good Clinical Practice and was approved by the institutional review board. Patients who met the inclusion and exclusion criteria had a baseline bronchoscopy, during which transbronchial and
Collagen deposition in peripheral and central airways
At baseline, there was a significant deposition of total collagen and collagen III in both peripheral and central airways. The percentage of the airway wall occupied by collagen as identified by Van Gieson stain for total collagen was significantly higher in central airways than in peripheral airways (54.5% ± 5.6% vs 37.7% ± 6.9%; P = .04; Fig 1, A). However, there were no significant differences between the percentage of the airway stained for collagen III in central airways compared with
Discussion
The current study describes the extent of collagen deposition and the smooth muscle mass in asthmatic peripheral airways by using transbronchial biopsies and addresses the effect of treatment with HFA-flunisolide on them. We observed structural similarities between central and peripheral airways. Both categories of airway had comparable amounts of collagen III deposition and α-smooth muscle actin. However, total collagen deposition was significantly higher in central airways compared with
References (46)
- et al.
Airways remodeling is a distinctive feature of asthma and is related to severity of disease
Chest
(1997) - et al.
Bronchial subepithelial fibrosis correlates with airway responsiveness to methacholine
Chest
(1997) - et al.
Subepithelial fibrosis in the bronchi of asthmatics
Lancet
(1989) - et al.
Airway inflammation and basement membrane tenascin in newly diagnosed atopic and nonatopic asthma
Respir Med
(2003) Airway smooth muscle: an immunomodulatory cell
J Allergy Clin Immunol
(2002)- et al.
Cytokine mRNA expression in asthma is not restricted to the large airways
J Allergy Clin Immunol
(1998) - et al.
Eotaxin and monocyte chemotactic protein-4 mRNA expression in small airways of asthmatic and nonasthmatic individuals
J Allergy Clin Immunol
(1999) - et al.
Airway remodeling-associated mediators in moderate to severe asthma: effect of steroids on TGF-beta, IL-11, IL-17, and type I and type III collagen expression
J Allergy Clin Immunol
(2003) - et al.
Effect of HFA-flunisolide on peripheral lung inflammation in asthma
J Allergy Clin Immunol
(2003) - et al.
The effect of transforming growth factor-beta on cell proliferation and collagen formation by lung fibroblasts
J Biol Chem
(1987)
Transforming growth factor-beta stimulates the expression of fibronectin and collagen and their incorporation into the extracellular matrix
J Biol Chem
Inhaled corticosteroids decrease subepithelial collagen deposition by modulation of the balance between matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 expression in asthma
J Allergy Clin Immunol
Effects of glucocorticoids and beta-adrenoceptor agonists on the proliferation of airway smooth muscle
Eur J Pharmacol
Interaction between glucocorticoids and beta2 agonists on bronchial airway smooth muscle cells through synchronised cellular signalling
Lancet
Airway remodeling in asthma
J Clin Invest
Bronchial biopsies in asthma: an ultrastructural, quantitative study and correlation with hyperreactivity
Am Rev Respir Dis
Enhanced proteoglycan deposition in the airway wall of atopic asthmatics
Am J Respir Crit Care Med
Tenascin is increased in airway basement membrane of asthmatics and decreased by an inhaled steroid
Am J Respir Crit Care Med
The measurement of reticular basement membrane and submucosal collagen in the asthmatic airway
Clin Exp Allergy
Collagen deposition in large airways may not differentiate severe asthma from milder forms of the disease
Am J Respir Crit Care Med
Eosinophil-associated TGF-beta1 mRNA expression and airways fibrosis in bronchial asthma
Am J Respir Cell Mol Biol
The relationship of reticular basement membrane thickness to airway wall remodeling in asthma
Am J Respir Crit Care Med
Small airways dimensions in asthma and in chronic obstructive pulmonary disease
Am Rev Respir Dis
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Supported by Canadian Institutes of Health Research, Forest Laboratories.