The Relationship Between Neutrophils Apoptotic Regulation And Pathogenesis Of Chronic Obstructive Pulmonary Disease

BackgroundNeutrophils play a vital role in constituting persistent inflammation of chronic obstructive pulmonary disease.Delayed neutrophils apoptosis maybe the one kind of reasons for persistent inflammation.As the most important regulators towords neutrophils apoptosis,Bcl-2 family members might be especially interested in it. The aim of our study was to detect Bcl-2 family members Bak,Bcl-xl and Mcl-1 mRNA expression of peripheral blood neutrophils in COPD patients compared with healthy volunteers. And then assess the relationship between the neutrophils apoptosis and pathogenesis of COPD.Patients9 mild to moderate COPD patients in stable stage,14 healthy smoking controls and 10 non-smoking controls with normal lung function.MethodsWe used discontinuous plasma-percoll gradients to isolate neutrophils from peripheral blood. Real-time PCR was used to measure the expression of Bak,Bcl-xl and Mcl-1 mRNA in peripheral blood neutrophils.ResultsReal-time PCR analysis showed a significant difference in the level of Bak,Bcl-xl and Mcl-1 mRNA Compared with healthy controls in peripheral blood neutrophils(All of the P value<0.05). Significant positive correlation between levels of Bak mRNA and FEV1,FEV1/FVC%were found(r=0.4388,P<0.05;r=0.4321,P<0.05). We also found good negative correlation between Bcl-xl and Mcl-1 mRNA expresstion levels and FEV1,FEV1/FVC%(r=-0.6851, p<0.001; r=-0.7908, p<0.001; r=-0.7726,p<0.001;r=-0.7467.p<0.001).ConclusionsOur study found significant diference in the levels of Bak,Bcl-xl and Mcl-1 mRNA in peripheral blood neutrophils of mild to moderahatte COPD patients compared with healthy controls.It indicated that one of the possible reasons of delayd neutrophils apoptosis in COPD is abnormal expression of Bcl-2 family members. We can suppose that Bcl-2 family has closely relationship with the development of COPD.In addition,the significant correlation between mRNA levels and lung function might be especially interested in severe degree of COPD.