Effect of Dexamethasone on Airway Hyperresponsiveness and Airway Inflammation in Ovalbumin-induced Murine Asthma Model.
- Author:
Dong Keun LEE
1
Author Information
1. Deparement of Pediatrics, Chung-Ang University College of Medicine, Seoul, Korea. zf41643@netsgo.com
- Publication Type:Original Article
- Keywords:
Asthma;
Dexamethasone;
Mice;
Bronchial hyperresponsiveness
- MeSH:
Animals;
Asthma*;
Bronchoalveolar Lavage Fluid;
Dexamethasone*;
Eosinophilia;
Eosinophils;
Female;
Gene Expression;
Glucocorticoids;
Humans;
Immunoglobulin E;
Inflammation*;
Injections, Intraperitoneal;
Leukocytes;
Lung;
Methacholine Chloride;
Mice;
Mucus;
Ovalbumin;
Ovum;
Transcription Factors
- From:Pediatric Allergy and Respiratory Disease
2003;13(3):162-170
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
PURPOSE: Glucocorticoids is the most effective therapy in the long-term control of asthma. It appears to reduce inflammation in asthmatic airways largely by inhibiting the action of transcription factors that regulate abnormal gene expression. But, the effect of the glucocorticoids on the bronchial hyperresponsiveness (BHR) is still controversial. The aim of this study is to investigate the effect of dexamethasone (DEX) on airway hyperresponsiveness and airway inflammation in Ovalbumin (OVA) -induced murine asthma model. METHODS: Female BALB/c mice were immunized with OVA and alum on day 0 and challenged intratracheally on days 8, 15, 18 and 21 with OVA. DEX, 1.5 mg/kg. And, they were administered 30 min after OVA challenges on day 15, 18 and 21 by intraperitoneal injection. BHR to methacholine measured 24 hours later after last OVA challenge and number of total leukocytes and eosinophils in the bronchoalveolar lavage fluid (BALF) was counted. Lung histomorphometry and measurement of total IgE concentration in the BALF were performed. RESULTS: Dexamethasone treatment did not change BHR to methacholine in this model. But it significantly reduced recruitment of leukocytes and eosinophils in the BALF. Eosinophilic inflammation and mucus plugging in lung tissues were significantly attenuated in the dexamethasone treated mice. Total IgE level in the BALF decreased by dexamethasone treatment. CONCLUSION: Dexamethasone treatment attenuates the eosinophilic inflammation but not the BHR in the murine asthma model. This study demonstrates the dissociation between airway eosinophilia and BHR by dexamethasone treatment.
