Background: Adiponectin, one of the adipokines, has been implicated in the inflammatory process in patients with allergic rhinitis. The level of adiponectin is affected by immunotherapy. Considering the fact that adiponectin receptors (AdipoRs) mediate intracellular signaling events in response to the binding of adiponectin, the role of AdipoRs in healthy and allergic nasal mucosa should be determined. This study investigates the level of expression and distribution pattern of AdipoR1 and AdipoR2 in healthy, mild, and moderate/severe persistent allergic nasal mucosa to understand the role of adiponectin in allergic rhinitis.
Methods: The level of expression and distribution pattern of AdipoR1 and AdipoR2 were evaluated in healthy, mild, and moderate/severe persistent allergic nasal mucosa, using semiquantitative reverse-transcriptase-polymerase chain reaction (RT-PCR), immunohistochemistry, and Western blot analysis.
Results: AdipoR1 was expressed in healthy, mild, and moderate/severe persistent allergic nasal mucosa where it was commonly localized to the vascular endothelium. However, AdipoR2 was not expressed in any samples of nasal mucosa tested in the present study. Semiquantitative RT-PCR and Western blot analysis showed that the level of expression of AdipoR1 mRNA and protein was decreased in mild and moderate/severe persistent allergic nasal mucosa in comparison with healthy nasal mucosa, but not significantly different between mild and moderate/severe persistent allergic nasal mucosa.
Conclusion: These results indicate that AdipoR1 may play an important role in the pathogenesis of allergic nasal mucosa, suggesting a role for AdipoR1 in vascular dysfunction in mild and moderate/severe persistent allergic nasal mucosa.