The Significance Of PAI-1, T-PA, U-PA And U-PAR Of Plasma And Sputum In Asthma

Objective: To detect the expression of PAI-1, t-PA, u-PA and u-PAR of plasma and sputum in asthma, compare the clinical significance of PAI-1,t-PA, u-PA and u-PAR in pathogenesis of acute attack asthmatics with asthma in stable stage. The correlation with pulmonary function was also investigated among them.Method: Plasma and induced sputum were isolated from 15 normal subjects(control group), 29 patients with acute attack of asthma(acute asthma group) and 26 stable patients(stable group). The concentrations of PAI-1, t-PA, u-PA and u-PAR were measured by enzyme linked immunosorbent assay. Meanwhile the pulmonary function(FEV1%pred ) of all groups were evaluated.Results: (1) The levels of u-PAR and PAI-1 of plasma were significantly increased in acute asthma group[(91.67±9.28) ng/ml, (0.650±0.154) ng/ml] compared with those in the control group[(59.80±16.88) ng/ml, (0.478±0.165 ng/ml)] (p<0.01); After treatment, levels of u-PAR and PAI-1 of plasma in the stable group[(84.15±14.60)ng/ml, (0.677±0.189)ng/ml]were still higher than those in control group (p<0.01). There were no differences of plasma concentrations of u-PA and t-PA among the acute asthma group [(0.098±0.020)ng/ml,( 24.47±10.23) ng/ml],stable group [(0.090±0.020)ng/ml, (22.63±7.24)ng/ml]and control group[(0.088±0.023)ng/ml,(26.14±6.32)ng/ml] (p>0.05).(2) The concentrations of sputum of u-PAR and PAI-1 were significantly increased in acute asthma group [(23.32±21.64)ng/ml, (0.766±0.272)ng/ml] compared with those in control group[(5.99±5.04)ng/ml,(0.516±0.197)ng/ml] (p<0.01) and were still higher than those in control group (p<0.05) after management [(17.23±9.40)ng/ml,(0.700±0.271)ng/ml]. As the induced sputum concentrations of u-PA and t-PA, there were no differences among the acute asthma group [(0.287±0.235)ng/ml,( 7.68±3.46)ng/ml], stable group[(0.251±0.276)ng/ml ,(9.88±4.68)ng/ml] and control group [(0.239±0.322)ng/ml,( 10.35±7.47)ng/ml] (p>0.05).(3) In stable group, the levels of plasma and induced sputum concentrations of PAI-1 had a negative correlation with the FEV1%pred( r is -0.659,-0.756,p<0.01).(4) In stable group, the level of plasma and induced sputum concentrations of PAI-1 had positive correlation with the length of disease course(r is 0.421,0.454 , p<0.05).Conclusions: These results suggested that there were high levels of PAI-1 and u-PAR in patients with acute asthma. After therapy, the levels of PAI-1 and u-PAR were still significantly higher than those in control group. The level of PAI-1 in stable group had a negative correlation with the FEV1%pred. The level of plasma and induced sputum concentrations of PAI-1 in stable group had positive correlation with the course of disease. All these suggested that PAI-1 and u-PAR might involve in pathophysiologic change of asthma.