Expression of RAGE and sRAGE in adenoidal hypertrophy with secretory otitis media in children

Objective: To investigate the expression of receptor for advanced glycation endproducts (RAGE) in adenoid hypertrophy in children and the change in the level of soluble receptor for advanced glycation endproducts (sRAGE) in tympanic effusion. Methods: Fifteen adenoidal specimens were collected from patients with adenoidal hypertrophy and secretory otitis media and patients with simple adenoidal hypertrophy without secretory otitis media who underwent surgical treatment at our hospital from April 2010 to December 2014. In addition, fifteen tympanic effusion specimens were collected from patients with simple secretory otitis media and from patients with adenoidal hypertrophy and secretory otitis media. Western blot analysis and immunohistochemistry were used to detect RAGE expression in adenoidal tissue, and an enzyme-linked immunosorbent assay (ELISA) was performed to determine the sRAGE levels in tympanic effusion. Results: Immunohistochemical staining showed that RAGE was expressed in each hypertrophic adenoidal tissue specimen and that RAGE protein expression levels were significantly higher in hypertrophic adenoidal tissue from patients with secretory otitis media than from those without secretory otitis media (P<0.05). Moreover, the sRAGE levels were significantly higher in tympanic effusion from patients with secretory otitis media and adenoidal hypertrophy than from patients with simple secretory otitis media (P<0.05). Conclusion: RAGE and sRAGE may play an important role in the pathogenesis of adenoidal hypertrophy with secretory otitis media.