Jang A S, Choi I S, Lee S, Seo J P, Yang S W, Park K O, Lee K Y, Lee J U, Park C S, Park H S
Department of Internal Medicine, Seonam University College of Medicine, Kwangju, Korea.
Clin Exp Allergy. 1999 Aug;29(8):1136-42. doi: 10.1046/j.1365-2222.1999.00595.x.
The role of nitric oxide (NO) needs to be further clarified in allergic inflammation. This study was designed to investigate the relationships between NO metabolites and eosinophil count, eosinophil cationic protein (ECP), interleukin (IL)-5 in induced sputum from asthmatics.
Hypertonic saline-induced sputum was obtained in 25 asthmatic subjects, among which 13 patients were examined before and after anti-asthmatic medications including steroid preparations. Ten normal subjects were enrolled as controls. Fresh expectorated sputum separated from saliva was treated with equal volume of dithiothreitol 0.1%, cytospinned for cell count, and the supernatant was collected for biochemical assay. NO metabolites were assayed by using modified Griess reaction. ECP was measured by fluoroimmunoassay, and detected IL-5 by a sandwich ELISA.
Asthmatic subjects, compared with controls, had significantly higher concentration of NO metabolites (1035.4 +/- 125.3 vs 557.2 +/- 101.5 micromol/L, P < 0.01), higher percentage of eosinophils (25.6 +/- 4.6 vs 1.7 +/- 0.2%, P < 0.01), and higher levels of ECP (1117.8 +/- 213.9 vs 154.6 +/- 47.4 microg/L, P < 0.01) in the induced sputum. IL-5 was detected more frequently in asthmatic subjects than in control subjects (11/25 [44%] vs 1/10 [10%], P < 0.05). According to asthma severity, moderate to severe asthmatic subjects (n = 18) had higher level of NO metabolites (1143.8 +/- 156.3 vs 575.5 +/- 89.5 micromol/L, P < 0. 01), higher levels of ECP and IL-5 (P < 0.01, respectively) in the induced sputum than in those of mild asthmatic subjects (n = 7). NO metabolites, the percentage of eosinophils, the levels of ECP, and IL-5 were reduced following treatment with anti-asthmatic drugs (P < 0.01, respectively). There were significant positive correlations between NO metabolites and percentage of eosinophils or ECP (r = 0. 34, P < 0.05; r = 0.28, P < 0.05). Negative correlations were noted between FEV1, FEV1/FVC and proportion of eosinophils, ECP, or IL-5 levels.
These findings confirmed that the level of NO metabolites was increased in the tracheobronchial secretion of asthmatic subjects and was paralleled with severity of asthma. Measurement of NO metabolites in induced sputum may be used for monitoring the degree of airway inflammation in asthmatics.
一氧化氮（NO）在变应性炎症中的作用尚需进一步阐明。本研究旨在探讨哮喘患者诱导痰中NO代谢产物与嗜酸性粒细胞计数、嗜酸性粒细胞阳离子蛋白（ECP）、白细胞介素（IL）-5之间的关系。
收集25例哮喘患者经高渗盐水诱导咳出的痰液，其中13例患者在使用包括类固醇制剂在内的抗哮喘药物治疗前后进行了检查。选取10名正常受试者作为对照。将咳出的新鲜痰液与唾液分离后，用等体积的0.1%二硫苏糖醇处理，经细胞离心涂片进行细胞计数，收集上清液进行生化检测。采用改良Griess反应检测NO代谢产物。用荧光免疫分析法测定ECP，采用夹心ELISA法检测IL-5。
与对照组相比，哮喘患者诱导痰中NO代谢产物浓度显著升高（1035.4±125.3 vs 557.2±101.5 μmol/L，P<0.01），嗜酸性粒细胞百分比更高（25.6±4.6 vs 1.7±0.2%，P<0.01），ECP水平更高（1117.8±213.9 vs 154.6±47.4 μg/L，P<0.01）。哮喘患者中检测到IL-5的频率高于对照组（11/25 [44%] vs 1/10 [10%]，P<0.05）。根据哮喘严重程度，中度至重度哮喘患者（n=18）诱导痰中NO代谢产物水平（1143.8±156.3 vs 575.5±89.5 μmol/L，P<0.01）、ECP和IL-5水平（分别为P<0.01）高于轻度哮喘患者（n=7）。抗哮喘药物治疗后，NO代谢产物、嗜酸性粒细胞百分比、ECP和IL-5水平均降低（分别为P<0.01）。NO代谢产物与嗜酸性粒细胞百分比或ECP之间存在显著正相关（r=0.34，P<0.05；r=0.28，P<0.05）。FEV1、FEV1/FVC与嗜酸性粒细胞比例、ECP或IL-5水平之间呈负相关。
这些发现证实哮喘患者气管支气管分泌物中NO代谢产物水平升高，且与哮喘严重程度平行。检测诱导痰中NO代谢产物可用于监测哮喘患者气道炎症程度。
