Mechanism of action of glucocorticoids in nasal polyposis.
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.
SourceAvailable from: Atila Gungor[Show abstract] [Hide abstract]
ABSTRACT: The aim of this study was to evaluate hydroxyproline levels in nasal specimens from patients with nasal polyps, and to examine hydroxyproline levels after nasal steroid spray and oral steroid treatments. This study was performed on 41 patients. The subjects were divided into four groups: no medication group (group A, n 11), oral methylprednisolone group (group B, n 8), topical steroid spray group (group C, n 8) and control group (group D, n 14). Nasal polyp samples were collected endoscopically. Healthy subjects were studied as a control group, and their nasal samples were taken during turbine reduction surgery. All samples were analyzed using the immunocytochemistry method. Hydroxyproline levels were investigated and compared with the control group. Mean hydroxyproline levels in groups A-D were 98.48, 24.20, 8.97 and 4.52, respectively. The hydroxyproline levels were significantly higher in group A compared with that of group D. The treatment that revealed significant decreases in hydroxyproline levels was group C. Although there was also a noticeable reduction in group B, there were no statistically significant differences between group B and group A. Our study revealed a significant correlation between nasal polyp and hydroxyproline levels. The hydroxyproline levels were significantly higher in nasal polyps. Both oral and topical steroid treatments decrease hydroxyproline levels in nasal polyps. Thus, in theory, steroid treatment can directly decrease hydroxyproline levels by inhibiting proline hydroxylase and indirectly by lowering the inflammatory process.Archives of Oto-Rhino-Laryngology 03/2011; 268(8):1147-50. DOI:10.1007/s00405-011-1546-6 · 1.61 Impact Factor
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ABSTRACT: Objective: To investigate endoscopic staging, and nitric oxide levels in the polyp tissue, in patients with nasal polyposis undergoing glucocorticoid therapy. Methods: Nasal polyposis was evaluated using endoscopic staging and measurement of polyp tissue nitric oxide levels (chemiluminescence method). Forty-five nasal polyposis patients received either nasal therapy (n = 15), oral therapy (n = 15) or combined therapy (n = 15). Pre-treatment and post-treatment staging and nitric oxide levels were evaluated. Results: Endoscopic grading indicated significant post-treatment staging improvements in the oral (p = 0.016) and combined (p = 0.016) groups. Post-treatment staging differed significantly between the three groups (p = 0.041), with greater improvements in the oral and combined groups. All groups showed significantly lower post-treatment nitric oxide levels, compared with baseline, but post-treatment levels did not differ significantly between groups. A significant association was found between treatment response and nitric oxide level alteration. Conclusion: This study demonstrates the favourable effects of glucocorticoids on nasal polyposis, and alteration in nitric oxide tissue levels post-treatment. Nitric oxide level in nasal polyp tissue could be an indicator of treatment response, and may aid surgical decision-making by detecting cases that probably will not respond to medical treatment.The Journal of Laryngology & Otology 04/2013; 127(6):1-6. DOI:10.1017/S002221511300073X · 0.70 Impact Factor
Pharmacotherapy, 1 01/2012: chapter 6: pages 115-140;