Investigation Of The Pathogenesis Of Lung Injury In COPD Patients Due To The Oxidants/antioxidants Imbalance

Objective: Investigate the mechanism of action of the oxidants/antioxidants imbalance in the COPD patients' chronic lung injury and find the theory support of the antioxidants therapy in the COPD patients through decreasing the airway chronic inflammation controlling the airway remodeling and improving the lung function.Methods: 50 COPD patients who were in stable phase were enrolled in this investigation according to the diagnose and therapy guideline of the chronic obstructive pulmonary disease in 2002. They all came from the medical outpatients of Tianjin General Hospital from January to May in 2004. They were divided into three groups: IIA group, II B group and III group.Superoxide dismutase (SOD), malondialdehyde (MDA) and nitric oxide (NO) in the blood were detected. The index of respiratory function FEV₁ , FEV₁/FVC , PEF MEF50%FVC% , MEF25%FVC%, the index of respiratory muscle function Punax%, Pemax% and airway resistance index R4Hz , R8Hz , R16F, the pro-inflammatory cytokines IL-1 β , IL-6 , IL-8 , TNF- a , TGF- β 1 in the blood were detected too. The different of the data was compared among the- three groups. Correlation analysis was did among MDA, TGF- β1 , respiratory function index and other cytokines. Results: MDA and TGF- 3 1 had negative correlation with lung ventilation index FEV₁ , FEV₁/FVC , PEF , MEF50%FVC% , MEF25%FVC% and respiratory muscle force index Pimax%(P<0.01) and had positive correlation with airway resistance index R8Hz which r=0.33 and 0.49 respectively(P<0.01). NO had positive correlation with lung ventilation index FEV₁, , FEV₁/FVC PEF MEF50%FVC% , MEF25%FVC% and respiratory muscle force index Pimax%(P<0.01) and had negative correlation with airway resistance index R4Hz , R8Hz(r=-0.39) , R16Hz(P<0.01). The pro-inflammatory cytokines had negative correlation with lung ventilation index FEV₁ , FE₁/FVC, PEF, MEF50%FVC% , MEF25%FVC% and respiratory muscle forceindex Pimax % (P<0.01) and had positive correlation with airway resistance index R8Hz (PO.01). MDA and TGF-3 1 had positive correlation with the pro-inflammatory cytokines IL-1 ï¿¡ nIL-8 ^TNF- a (PO.01) and had negative correlation with NO which r=-0.83 and -0.84 respectively(P<0.01). NO had negative correlation with the pro-inflammatory cytokines IL-1 P > IL-8 s TNF-a (PO.01). MDA had positive correlation with TGF- P 1 (r=0.80,P<0.01).Conclusion: Degree of lung injury in the COPD patients has correlation with the level of the oxidation in the lung. The pro-inflammatory cytokines IL-1 P > IL-6 n IL-8 > TNF-a and TGF- 3 1 have great effects to the chronic lung injury. The oxidants can make the airway chronic inflammation and airway remodeling existing persistently through enhance the express of the pro-inflammatory cytokines IL-1 P ^ IL-6 > IL-8 > TNF- a and TGF- P 1 besides its direct injury. The available antioxidants give us a hope to lessen the chronic lung injury and slow down the progress of the lung function's descent.