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Published on: September 15, 2017
Effect of beta-agonists on inflammatory cells.
1Department of Thoracic Medicine, National Heart and Lung Institute, Imperial College, London, UK.
The Journal of Allergy and Clinical Immunology
|August 19, 1999
Summary
Beta(2)-agonists relax airway smooth muscle and inhibit inflammatory mediators. However, they do not reduce chronic asthma inflammation, possibly due to receptor desensitization.
Area of Science:
- Pharmacology
- Immunology
- Respiratory Medicine
Background:
- Beta(2)-agonists primarily relax airway smooth muscle via beta(2)-adrenergic receptors.
- These receptors are also present on various non-airway smooth muscle cells, influencing inflammatory responses.
Purpose of the Study:
- To explore the diverse effects of beta(2)-agonists beyond bronchodilation.
- To investigate the role of these additional actions in asthma symptom relief.
- To understand the impact of beta(2)-agonists on airway inflammation and mediator release.
Main Methods:
- Review of existing literature on beta(2)-agonist mechanisms.
- Analysis of in vitro studies detailing effects on inflammatory cells.
- Examination of receptor expression and desensitization phenomena.
Main Results:
- Beta(2)-agonists inhibit plasma exudation, mediator release from mast cells, eosinophils, and other immune cells.
- They may also inhibit neuropeptide release from sensory nerves.
- Despite in vitro anti-inflammatory effects, beta(2)-agonists do not reduce chronic asthma inflammation.
Conclusions:
- Beta(2)-agonist efficacy in asthma involves multiple anti-inflammatory actions.
- Receptor desensitization in inflammatory cells may explain the lack of effect on chronic inflammation.
- Corticosteroids may enhance beta(2)-receptor expression to counteract desensitization.
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