RESUMO
OBJECTIVES: To investigate the expression of peroxisome proliferator-activated receptor gamma (PPAR-gamma) messenger RNA and protein and to localize the PPAR-gamma protein in the nasal mucosa of patients with allergic rhinitis and control subjects. DESIGN: Prospective study. SETTING: Tertiary academic institution. Patients Twenty patients with perennial allergic rhinitis and 20 matched nonallergic patients. INTERVENTIONS: Inferior turbinate mucosa samples were obtained from 20 patients with perennial allergic rhinitis and 20 matched nonallegic patients. Peroxisome proliferator-activated receptor gamma messenger RNA was extracted from the inferior turbinate mucosae, and then reverse transcription-polymerase chain reaction was performed. Western blot testing was used to analyze differences in PPAR-gamma protein expression levels between patients with allergic rhinitis and normal controls, and the PPAR-gamma protein was localized immunohistochemically. RESULTS: The expression levels of PPAR-gamma messenger RNA and protein in the nasal mucosa was significantly increased in patients with perennial allergic rhinitis compared with controls. Peroxisome proliferator-activated receptor gamma protein was expressed in the epithelium, infiltrating inflammatory cells, and submucosal glands. CONCLUSIONS: Peroxisome proliferator-activated receptor gamma is expressed in the human nasal mucosa and is up-regulated in perennial allergic rhinitis. These results suggest a possible contribution for PPAR-gamma in chronic inflammation of the nasal mucosa in perennial allergic rhinitis.