Effect of Inhaled Budesonide on Interleukin-4 and Interleukin-6 in Exhaled Breath Condensate of Asthmatic Patients / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Studies of interleukin (IL)-4 and IL-6 in the exhaled breath condensate (EBC) of asthmatic patients are limited. This study was to determine the effect of inhaled corticosteroid (ICS) treatment on IL-4 and IL-6 in the EBC of asthmatic patients.</p><p><b>METHODS</b>In a prospective, open-label study, budesonide 200 μg twice daily by dry powder inhaler was administered to 23 adult patients with uncontrolled asthma (mean age 42.7 years) for 12 weeks. Changes in asthma scores, lung function parameters (forced expiratory volume in 1 s [FEV1], peak expiratory flow [PEF], forced expiratory flow at 50% of forced vital capacity [FEF50], forced expiratory flow at 75% of forced vital capacity, maximum mid-expiratory flow rate) and the concentrations of IL-4 and IL-6 in EBC were measured.</p><p><b>RESULTS</b>Both asthma scores and lung function parameters were significantly improved by ICS treatment. The mean IL-4 concentration in the EBC was decreased gradually, from 1.92 ± 0.56 pmol/L before treatment to 1.60 ± 0.36 pmol/L after 8 weeks of treatment (P < 0.05) and 1.54 ± 0.81 pmol/L after 12 weeks of treatment (P < 0.01). However, the IL-6 concentration was not significantly decreased. The change in the IL-4 concentration was correlated with improvements in mean FEV1, PEF and FEF50 values (correlation coefficients -0.468, -0.478, and -0.426, respectively).</p><p><b>CONCLUSIONS</b>The concentration of IL-4 in the EBC of asthmatic patients decreased gradually with ICS treatment. Measurement of IL-4 in EBC could be useful to monitor airway inflammation in asthmatics.</p>

Effects of N-acetylcysteine on Clara cells in rats with cigarette smoke exposure / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The number of Clara cells and the Clara cell 16-kDa protein (CC16) levels of the lung decrease in patients with chronic obstructive pulmonary disease (COPD). N-acetylcysteine (NAC) is a powerful antioxidant and can reduce the frequency of acute exacerbations of COPD. But the exact mechanism is unclear. The present study was designed to investigate the effects of NAC on Clara cells in rats with cigarette smoke exposure.</p><p><b>METHODS</b>Eighteen adult male Wistar rats were randomly divided into 3 groups, 12 exposed to cigarette smoke (CS) thrice a day, 10 cigarettes for 30 minutes each time for 1 week, without (CS group) or with (CS + NAC group) oral intake of NAC 80 mg x kg(-1) x d(-1), and another 6 rats exposed to fresh air (control group). Clara cells were observed by an electron microscope. The mRNA expression of CC16 and CC16 protein in lungs were determined by reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemistry respectively. The glutathion (GSH) level in plasma and lung tissue were tested by fluorimetry assay.</p><p><b>RESULTS</b>Compared with the controls, the pathologic score of small airways significantly increased in the CS exposed rats (20.3 +/- 14.7 vs. 53.7 +/- 11.5, P < 0.05). The Clara cell particles in cytoplasm decreased in the CS group (P < 0.05). The percentage of CC16-positive cells in bronchioles in the CS group (27.8 +/- 4.3 and 29.5 +/- 2.4 in terminal bronchioles and respiratory bronchioles, respectively) significantly decreased as compared with the control group (37.1 +/- 3.8 and 43.8 +/- 5.8 in terminal bronchioles and respiratory bronchioles, respectively) (P < 0.05). No significant difference was observed in GSH level ((181 +/- 26) nmol/L in the control group vs. (170 +/- 18) nmol/L in the CS group) between the two groups. After treatment with NAC, the pathologic score of small airways (24.1 +/- 17.5) decreased (P < 0.05). Clara cell particles in cytoplasm of Clara cells increased and GSH level in plasma ((213 +/- 40) nmol/L vs. (170 +/- 18) nmol/L in the CS group) increased too (P < 0.05), while the increase in the proportions of CC16 positive cells in bronchioles (30.1 +/- 6.4 and 34.3 +/- 6.3 in terminal bronchioles and respiratory bronchioles, respectively) did not reach the statistical significance (P > 0.05). No significant difference was found in the expression of CC16 mRNA among the three groups. Correlation analysis indicated that the percentage of CC16-positive cells in bronchioles negatively correlated with the pathologic score of small airways (r = -0.592, P < 0.05), but not with GSH level.</p><p><b>CONCLUSIONS</b>One-week CS exposure decreased the number of Clara cells and the expression of CC16 in bronchioles in rats. NAC might provide protection of the Clara cells from oxidative damage and possibly through the elevation of the synthesis and secretion of CC16. These data indicate that NAC decreases airway inflammation induced by CS via induction of CC16.</p>