哮喘患儿血红素氧合酶-1活性的变化及其意义

Determination of heme oxygenase-1 activity and its clinical signification in children with asthma

目的 观察哮喘发作期、缓解期哮喘患儿血红素氧合酶 1(HO 1)活性的变化及其意义。方法 采用分光光度法等方法 ,对轻～重度哮喘患儿 (72例 )在发作期和缓解期 (72例中的 34例 )分别检测血清HO 1活性、血一氧化碳血红蛋白 (COHb)、一氧化氮 (NO) ,环 磷酸鸟苷 (cGMP)、IgE水平 ,并与对照组 (32例 )健康儿进行比较。结果 (1)哮喘组HO 1活性为 (12 7± 33)nmol/(h·L) ,正常组为(39± 13)nmol/(h·L) ,缓解组为 (34± 14)nmol/(h·L) ,哮喘组与正常组、缓解组差异均有显著意义(t=19.87,15 .5 9,P <0 .0 1) ;哮喘病情严重度 (轻、中、重 )之间HO 1活性差异亦有显著意义(F =76 .5 9,P <0 .0 1)。 (2 )哮喘组血COHb、NO、cGMP和IgE均高于正常组 ,差异有非常显著意义(P <0 .0 1) ,与缓解组差异亦有显著意义 (P <0 .0 1) ,且分别与HO 1活性呈显著正相关 (r=0 .8774、0 .7772、0 .745 1、0 .7915 ,P <0 .0 0 1) ;缓解组上述指标与正常组之间差异无显著意义 (P >0 .0 5 )。结论 哮喘发作时患儿体内的HO 1活性增加 ,与体内内源性一氧化碳、NO、cGMP和IgE水平增加相关。HO活性水平可反映哮喘病情的严重程度。

Objective To observe the change of heme oxygenase 1 (HO 1) activity in children with symptomatic and asymptomatic or stable asthma and determine whether HO 1 contributes to the mechanism of allergic asthma and thereby to evaluate its possible application in clinical practice. Methods In the early morning, 2 ml venous blood was collected from all enrolled subjects, including 72 children with critical or mild symptomatic asthma (male 43, female 29, and age 6.5±3.1 years), 34 asymptomatic cases of the 72 children who were at the relieving stage (relieved asthma group, male 19, female 15, and age 6.7±3.2 years) and 32 healthy children who were enrolled to serve as normal controls (male 18, female14, and age 6.3±3.1 years). The levels of HO 1 activity, COHb and NO were measured with the double wavelength scanning by a spectrophotometer; cGMP and IgE by using [125] I cGMP and total IgE with EIA avidine biotine radioimmunoassay kits. Results The HO 1 activities [127±33 nmol/(h·L)] in children with symptomatic asthma were markedly higher than that of normal control subjects [34±14 nmol/(h·L)] (t=19.87, P<0.01). There were distinct differences among subjects with different degrees of symptomatic asthma (F=76.59, P< 0.01 by the F test of multiple groups). The levels of COHb, NO, cGMP and IgE in asthmatic children also elevated as compared with normal control subjects (P<0.01) and positively correlated to the level of HO 1 activity, respectively (r=0.877 4, 0.777 2, 0.745 1, 0.791 5,P<0.001). All the tested levels in the 34 cases during asymptomatic phase of asthma recovered to normal compared with the levels obtained during symptomatic phase of asthma [for example, HO 1 activity was(39±13)nmol/(h·L),t=15.59, P<0.01 by the paired t test]. Conclusions The increased activity of HO 1 in children with asthma was positively related to their levels of endogenous CO, cGMP, NO and IgE. This suggests that HO 1 activity may reflect inflammation in the asthmatic lung and therefore may serve as a reference index for diagnosing asthma and evaluating therapeutic effects.