Resveratrol prevents development of eosinophilic rhinosinusitis with nasal polyps in a mouse model.

BACKGROUND: Since the recent establishment of a murine model of eosinophilic chronic rhinosinusitis with nasal polyps (CRSwNP), both the development of new drugs for treatment or prevention of eosinophilic CRSwNP and elucidation of their pathogenesis have been feasible. We investigated the therapeutic effects of resveratrol on CRSwNP and its mechanism of action using a murine model. METHODS: After induction of eosinophilic CRSwNP, the therapeutic effects of resveratrol were tested and compared with those of triamcinolone acetonide. Histopathologic changes were evaluated using hematoxylin and eosin for overall inflammation, Sirius red for eosinophils, and Masson's trichrome stain for collagen. The expression levels of the interleukin (IL)-4, IL-5, prostaglandin D synthase, and leukotriene C4 synthase genes were assessed by quantitative real-time PCR. Cyclooxygense-2 and 5-lipoxygense levels were evaluated by immunohistochemical staining and Western blot analysis. RESULTS: The degree of eosinophilic infiltration and subepithelial fibrosis was significantly decreased by administration of high-dose resveratrol, the potency of which was similar to that of triamcinolone acetonide. The expression levels of the IL-4, IL-5, prostaglandin D synthase, and leukotriene C4 synthase genes were significantly decreased by administration of low- or high-dose resveratrol. The production of 5-lipoxygenase was strongly inhibited by high-dose resveratrol. CONCLUSIONS: Resveratrol may be useful for the prevention of eosinophilic CRSwNP. A key mechanism of its action is believed to be its anti-inflammatory effect, particularly on eosinophils, by inhibiting the lipoxygenase pathway.

Erectile dysfunction and disease-specific quality of life in patients with obstructive sleep apnea.

Several reports have suggested a high incidence of erectile dysfunction (ED) among patients with obstructive sleep apnea syndrome (OSAS). The aim of this study was to investigate the correlation between OSAS and ED, or disease-specific quality of life (QOL) in patients with OSAS. In addition, we analyzed specific polysomnographic (PSG) parameters in predicting ED in OSAS patients. In total, 32 patients with OSAS and 27 normal controls were asked to complete the Korean versions of the International Index of Erectile Function questionnaire (KIIEF-5) and the Calgary Sleep Apnea Quality of Life Index (SAQLI). All patients then underwent a full-night in-laboratory PSG examination. Patients were diagnosed with OSAS if they had clinical symptoms suggestive of OSAS for at least 1 year and an apnea-hypopnea index (AHI) of more than 10 in PSG. Nineteen patients (59.3%) in the OSAS group showed ED, which was significantly higher than in the control group (8 patients, 29.6%, P=0.012). In addition, SAQLI scores worsened as AHI increased (r=0.327, P=0.011) and as the lowest oxygen saturation level decreased (r=0.420, P=0.001). ED was not significantly correlated with AHI (r=0.061, P=0.649); however, it was significantly correlated with the lowest oxygen saturation decreased (r=0.338, P=0.009). When the cutoff value for the lowest oxygen saturation level to predict ED was set at 77%, its positive predictive value was 88.9% (sensitivity=0.70, specificity=0.62). Thus, all male patients with OSAS should be screened for erectile dysfunction and more comprehensive consultation is needed, especially, if their lowest oxygen saturation levels are below 77%.

Bronchial hyperresponsiveness in young children with allergic rhinitis and its risk factors.

BACKGROUND: Subjects with allergic rhinitis but no clinical evidence of asthma have greater bronchial hyperresponsiveness (BHR), and several factors have been implicated as its determinants. However, studies in young children are lacking. The aims of this study were to evaluate the prevalence of BHR in young children with allergic rhinitis and to investigate its risk factors. METHODS: Methacholine bronchial challenges were performed in 4- to 6-year-old nonasthmatic children with allergic rhinitis (n = 83) and in healthy nonatopic controls (n = 32), using a modified auscultation method. The end-point was defined as the appearance of wheezing and/or oxygen desaturation. Subjects were considered to have BHR when they had end-point concentrations of methacholine

The importance of maximal airway response to methacholine in the prediction of asthma development in patients with allergic rhinitis.

BACKGROUND: Allergic rhinitis is a known predictor and correlate of asthma incidence. However, it is not clear which patients with allergic rhinitis are at greater risk of the development of asthma. OBJECTIVE: The aim of this study was to investigate whether airway hypersensitivity and/or increased maximal response on the dose-response curve to methacholine would predict the development of asthma in subjects with allergic rhinitis. METHODS: One hundred and forty-one children with allergic rhinitis were prospectively studied for 7 years. At the initiation of the study, bronchial provocation test with methacholine using a stepwise increasing concentration technique was performed to measure PC(20) (provocative concentration causing a 20% fall in FEV(1)) and maximal response. Each subject was evaluated at least every 6 months and details of asthmatic symptoms or signs experienced during the intervening period were taken. RESULTS: Twenty of 122 subjects available for the follow-up developed asthma. Nine (19.6%) of 46 hypersensitive (PC(20) < 18 mg/mL) subjects developed asthma, compared with 11 (14.5%) of 76 normosensitive subjects (P = 0.462). Eight (32%) of 25 subjects without maximal response plateau developed asthma, compared with 12 (12.4%) of 97 subjects with maximal response plateau (P = 0.018). Score test for trend revealed a significant association between the level of maximal response (P = 0.007), but not the degree of methacholine PC(20) (P = 0.123), and the future development of asthma. CONCLUSION: An increased maximal airway response to methacholine is shown to be a better predictor for the future development of asthma in patients with allergic rhinitis, than airway hypersensitivity to methacholine.