ABSTRACT
Objective To explore the correlation between the expressions of matrix metalloproteinase -9 (MMP-9), Toll-likeReceptor 4 ( TLR4) and lung revascularization in patients with chronic obstructive pulmonary disease .Methods Lung tissues frompatients with chronic obstructive pulmonary disease (COPD) (COPD group,n =25) and those without COPD (non-COPD group,n =25) were obtained from surgically resected specimens .The ratio of the area of the wall to that of the pulmonary arterioles (WA %) andthe ratio of the thickness of the wall to the external diameter of the pulmonary arterioles (WT %) were analyzed by computer-based imageanalysis system.Immunohistochemical technique was applied to investigate the expressions of TLR 4, proliferative cell nuclear antigen(PCNA) and MMP-9 in vascular smooth muscle cells.Results ⑴ The inflammatory infiltration degree, WA %, and WT %were significantly higher than that of non -COPD group ( P <0.01), respectively.⑵Compared with non-COPD group, the expressionsof PCNA, TLR4, and MMP-9 in vascular smooth muscle cells were increased significantly ( P <0.01).⑶The expressions of TLR4,MMP-9 had a positive correlation with WA%, WT%, degree of inflammatory infiltration, and the expression of PCNA ( r =0.67,0.74,0.47,0.44;0.59,0.71,0.61,0.33, P <0.01), up-regulated expression of TLR4 was closely related with the expression of MMP-9 ( r =0.55, P <0.01).Conclusions The pulmonary arterioles of COPD patients showed marked inflammatory and arteriolemuscularization, the TLR4 might aggravate inflammation,induced upregulation of MMP-9 expression, played an important role in the pulmonary vascular remodeling process.