Back to Search
Start Over
Inhaled corticosteroid reduced lamina reticularis of the basement membrane by modulation of insulin-like growth factor (IGF)-I expression in bronchial asthma.
- Source :
-
Clinical and experimental allergy : journal of the British Society for Allergy and Clinical Immunology [Clin Exp Allergy] 1998 May; Vol. 28 (5), pp. 568-77. - Publication Year :
- 1998
-
Abstract
- Background: Pathological studies of bronchial biopsy specimens have confirmed the apparent thickening of lamina reticularis of the epithelial basement membrane. Corticosteroids have proven to be most effective in modifying airway inflammation. However, there is not much data on the effects of corticosteroid-treatment on the basement membrane.<br />Objective: To investigate the effects of inhaled beclomethasone dipropionate (BDP) on the thickness of basement membrane and cellular infiltration into the bronchial mucosa, and the expression of growth factors in patients with asthma.<br />Methods: We studied bronchial biopsies from 24 asthmatic patients before and after treatment with inhaled BDP, 400 microg twice a day or placebo, for 6 months in a double-blind manner. Each subject recorded daily asthma symptoms and peak expiratory flow (PEF). Lung function and bronchial responsiveness to methacholine were measured before and after treatment. The thickness of the basement membrane was determined by electron microscopy. Inflammatory cells and the expression of growth factors were examined by immunohistochemistry in endobronchial biopsy specimens.<br />Results: After 6 months of treatment, we observed a significant improvement of asthma symptoms (P<0.01), PEF (P<0.01), diurnal variation of PEF (P<0.05), and airway responsiveness (P< 0.05) in the BDP group compared with the placebo group. This was accompanied by a significant decrease in the thickness of the lamina reticularis (P < 0.001), and in the number of activated eosinophils (P<0.01), T-lymphocytes (P<0.01), and fibroblasts (P < 0.05) in BDP-treated patients. There was also a reduction in the expression of insulin-like growth factor (IGF)-I (P < 0.01). Significant correlation was found between the IGF-I expression and collagen thickening (rs = 0.34, P<0.01), and the number of fibroblasts (rs = 0.45, P < 0.01).<br />Conclusion: These results suggest that corticosteroid treatment in asthma can reduce the lamina reticular thickness by modulation of IGF-I expression with consequent inhibition of the airway infiltration by inflammatory cells, and therefore may help to prevent remodelling of the airways.
- Subjects :
- Administration, Inhalation
Adolescent
Adult
Anti-Asthmatic Agents administration & dosage
Asthma metabolism
Asthma pathology
Basement Membrane pathology
Beclomethasone administration & dosage
Bronchi metabolism
Bronchoscopy
Double-Blind Method
Forced Expiratory Volume
Humans
Inflammation
Microscopy, Electron
Middle Aged
Mucous Membrane pathology
Peak Expiratory Flow Rate
Anti-Asthmatic Agents therapeutic use
Asthma drug therapy
Beclomethasone therapeutic use
Bronchi pathology
Insulin-Like Growth Factor I biosynthesis
Subjects
Details
- Language :
- English
- ISSN :
- 0954-7894
- Volume :
- 28
- Issue :
- 5
- Database :
- MEDLINE
- Journal :
- Clinical and experimental allergy : journal of the British Society for Allergy and Clinical Immunology
- Publication Type :
- Academic Journal
- Accession number :
- 9645593
- Full Text :
- https://doi.org/10.1046/j.1365-2222.1998.00277.x