[Expressions of OB-R, IRF-1 and GR-ß in airway smooth muscle cells of obese rats with asthma].

AIM: To explore the relationship between obesity and difficult-to-treat asthma by observing the expressions of leptin receptor (OB-R), interferon regulatory factor-1 (IRF-1) and glucocorticoid receptor-ß (GR-ß) in airway smooth muscle cells (ASMCs) of obese rats with asthma. METHODS: Sixty rats were randomly divided into 4 groups, 2 groups with normal weight: control group (group A), asthmatic group (group B), and 2 groups with obesity: control group (group C), asthmatic group (group D). The trachea smooth muscle was obtained from the rats of each group, and ASMCs were isolated, purified, and cultured in vitro. Then the expression of OB-R mRNA was measured by RT-PCR, and the levels of IRF-1 and GR-ß proteins were measured by Western blotting. RESULTS: The expression of OB-R mRNA in airway smooth muscle cells in group B, C and D were higher than that in group A, while it in group D was significantly higher than group B and C. What's more, the levels of IRF-1 and GR-ß proteins increased in group B, C and D as compared with group A, and were significantly higher in group D than in group B and C, respectively. CONCLUSION: The increased expressions of OB-R, IRF-1 and GR-ß in ASMCs of obese rats with asthma may play a role in the onset of obese asthma and glucocorticoid resistance.