Mechanism of action of glucocorticoids in nasal polyposis.

Doutorado USP/Ribeirão Preto, Brazil.
Brazilian journal of otorhinolaryngology (Impact Factor: 0.62). 04/2008; 74(2):279-83.
Source: PubMed

ABSTRACT Glucocorticoids (GC) are the drugs of choice for the clinical treatment of nasal polyposis, according to the medical literature. Its mechanism of action in the regression of clinical symptoms and polyps, however, is not fully understood. The topical and/or systemic use of glucocorticoids lead to variable expression of cytokines, chemokines and lymphokines, as well as changes in cells. It is known that GC suppresses the expression of pro-inflammatory cytokines, chemokines and adhesion molecules such as ICAM-1 and E-selectin; GC also stimulate the transcription of anti-inflammatory cytokines such as TGF-b. GC suppress pro-fibrotic cytokines related to polyp growth, such as IL-11, the basic fibroblast growth factor (b-FGF), and the vascular endotelial growth factor (VEGF). The action of GC depends fundamentally on their interaction with receptors (GR); certain subjects have a degree of resistance to its effect, which appears to be related with the presence of a b isoform of GR. GC also act variably on the genes involved in immunoglobulin production, presentation, and antigen processing. AIM: We present a review of the literature on the mechanisms of GC action in nasal polyosis. CONCLUSION: Understanding the mechanism of action of GC in nasal polyposis will aid in the development of new, more efficient, drugs.

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