pulmicort and Pulmonary-Fibrosis

Chlorine is a chemical threat agent that can be harmful to humans. Acute inhalation of high levels of chlorine results in the death of airway epithelial cells and can lead to persistent adverse effects on respiratory health, including airway remodeling and hyperreactivity. We previously developed a mouse chlorine exposure model in which animals developed inflammation and fibrosis in large airways. In the present study, examination by laser capture microdissection of developing fibroproliferative lesions in FVB/NJ mice exposed to 240 ppm-h chlorine revealed upregulation of genes related to macrophage function. Treatment of chlorine-exposed mice with the corticosteroid drug budesonide daily for 7 days (30-90 μg/mouse i.m.) starting 1 h after exposure prevented the influx of M2 macrophages and the development of airway fibrosis and hyperreactivity. In chlorine-exposed, budesonide-treated mice 7 days after exposure, large airways lacking fibrosis contained extensive denuded areas indicative of a poorly repaired epithelium. Damaged or poorly repaired epithelium has been considered a trigger for fibrogenesis, but the results of this study suggest that inflammation is the ultimate driver of fibrosis in our model. Examination at later times following 7-day budesonide treatment showed continued absence of fibrosis after cessation of treatment and regrowth of a poorly differentiated airway epithelium by 14 days after exposure. Delay in the start of budesonide treatment for up to 2 days still resulted in inhibition of airway fibrosis. Our results show the therapeutic potential of budesonide as a countermeasure for inhibiting persistent effects of chlorine inhalation and shed light on mechanisms underlying the initial development of fibrosis following airway injury.

Topics: Acute Lung Injury; Animals; Budesonide; Cell Differentiation; Chlorine; Disease Models, Animal; Epithelial Cells; Female; Glucocorticoids; Humans; Inflammation; Inhalation Exposure; Laser Capture Microdissection; Mice; Pulmonary Fibrosis; Respiratory Mucosa; Treatment Outcome

To observe the effect of Budesonide (BUD) on TGF-β1, PDGF-A, Smad4 and PAI-1 in lung tissue in pulmonary fibrosis rats.. Forty-five adult female Wistar rats were randomly divided into normal solution (NS) group, BUD group and bleomycin (BLM) group. 9 g/L NaCl solution was instilled into the tratracheaes in NS group, and BLM were used in BUD group and BLM group. NS group and BLM group were inhaled with 9 g/L NaCl solution once everyday at day 0-6, and BUD group were used with BUD. Five rats in every group were killed at 7th, 14th 28th day. The appearances of alveolitis and fibrosis were displayed in HE and Masson staining. The expressions of TGF-β1, PDGF-A, Smad4 and PAI-1 in lung tissue were detected by immunohistochemistry.. The extent of the alveolitis in BUD group at 7th, 14th day were significantly lower than that in BLM group(P<0.05). The fibrosis and the expressions of TGF-β1, PDGF-A, Smad4 and PAI-1 in lung tissues at 7th, 14th, 28th day, BUD group were significantly lower than BLM group(P<0.05).. After inhaled BUD, the expressions of TGF-β1, PDGF-A, Smad4 and PAI-1 in lung tissue could be decreased, and the extent of alveolitis and pulmonary fibrosis could be improved in bleomycin-induced pulmonary fibrosis rats.

Topics: Animals; Anti-Inflammatory Agents; Budesonide; Disease Models, Animal; Female; Plasminogen Activator Inhibitor 1; Platelet-Derived Growth Factor; Pulmonary Fibrosis; Rats; Rats, Wistar; Smad4 Protein; Transforming Growth Factor beta1