title: TGFβ-induced matrix production by bronchial fibroblasts in asthma: budesonide and formoterol effects.
abstract: To investigate the mechanisms of enhanced airway deposition of subepithelial collagen in asthma and its sensitivity to drug therapy with combination of an inhaled glucocorticosteroid (GC) and a long-acting β(2)-agonist (LABA), a cell model system involving bronchial fibroblasts derived from biopsies from patients with stable mild-to-moderate asthma has been used. To mimic unstable conditions and severe asthma, fibroblasts were stimulated ex vivo with TGFβ1. Primary fibroblasts established from central bronchial biopsies from 8 asthmatic patients were incubated for 24 h with 0.4% serum or TGFβ1 (10 ng/ml) with/without the GC budesonide (BUD; 10 nM) and/or the LABA formoterol (FORM; 0.1 nM). Procollagen peptide I (PICP), metalloproteinase (MMP)-1 and tissue inhibitor of MMPs (TIMP-1) were determined in culture media using ELISA while the activity of MMP-2, -3, -9 by zymography. Metabolically labeled proteoglycans, biglycan and decorin, associated with collagen fibrillation/deposition, were separated using chromatography and SDS-PAGE. The levels of PICP and biglycan were increased 2-fold by TGFβ1 (p < 0.05). The BUD and FORM combination reduced the PICP increase by 58% (p < 0.01) and the biglycan by 36% (p < 0.05) while each drug alone had no effect. Decorin levels were reduced by TGFβ1 in fibroblasts of most patients; BUD alone and BUD and FORM completely counteracted this decrease. MMPs and TIMP-1 were not affected by TGFβ1 or the drugs. These results suggest that BUD and FORM combination therapy, without affecting metalloproteolytic balance, has a potential to counteract enhanced collagen production by bronchial fibroblasts in asthma and to normalize the production of small proteoglycans which may affect collagen fibrillation and deposition.
authors.affiliation: Department of Experimental Medical Sciences, Division of Lung Biology, Lund University, BMC D12, 221 84 Lund, Sweden.
authors.forename: Lizbet
authors.initials: L
authors.lastname: Todorova
authors.forename: Leif
authors.initials: L
authors.lastname: Bjermer
authors.forename: Gunilla
authors.initials: G
authors.lastname: Westergren-Thorsson
authors.forename: Anna
authors.initials: A
authors.lastname: Miller-Larsson
mesh_terms: D000280:Administration, Inhalation; D000328:Adult; D001249:Asthma / Q000188:drug therapy / Q000378:metabolism; D001980:Bronchi / Q000187:drug effects* / Q000473:pathology; D001993:Bronchodilator Agents / Q000008:administration & dosage / Q000494:pharmacology*; D019819:Budesonide / Q000008:administration & dosage / Q000494:pharmacology*; D002845:Chromatography; D003094:Collagen / Q000187:drug effects / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D004983:Ethanolamines / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D005347:Fibroblasts / Q000187:drug effects* / Q000473:pathology; D000068759:Formoterol Fumarate; D006801:Humans; D008297:Male; D008875:Middle Aged; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000187:drug effects / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000187:drug effects* / Q000378:metabolism
chemical_list: D001993:Bronchodilator Agents; D004983:Ethanolamines; D019715:Tissue Inhibitor of Metalloproteinase-1; D016212:Transforming Growth Factor beta; D019819:Budesonide; D003094:Collagen; D000068759:Formoterol Fumarate