Objective: To explore the effect of modified Yupinfeng San (MYS) on the pathological morphology of chronic obstructive pulmonary disease(COPD) airway remodeling

and its regulatory effect on relevant cytokines matrix metalloproteinases-9(MMP-9)

tissue inhibitors metalloproteinases-1(TIMP-1) and transforming growth factor-β1(TGF-β1). Method: Totally 60 SD rats were selected. Except for 10 rats in the normal group

all of the remaining rats were included in the COPD animal model by means of smoking and lipopolysaccharide dripping and overlaying method. After the successful modeling

the rats were randomly divided into the model group

MYS high

middle and low-dose groups

and the positive drug group (Roxithromycin capsules). After the administration for 30 days

rat lung tissues were collected to prepare pathological slices. HE staining was used to observe histopathological changes in lung tissues

and ELISA method was adopted to detect MMP-9

TIMP-1 and TGF-β1 in rat bronchalveolar lavage fluid (BALF). Result: Compared with the normal group

the model group showed significant changes in lung tissue pathology morphology (P<0.05)

with mucosal hyperemia and edema on bronchial walls

significant inflammatory cell infiltration in alveolar macrophages(AM)

neutrophil(NEU)

lymphocyte(LYM) and eosnophils(EOS)

and significant increases in MMP-9

TIMP-1 and TGF-β1 expression levels (P<0.05); compared with the model group

MYS groups showed lodging

adhesion and missing in lung cilia

epithelial cell necrosis and detachment

and alleviation in bronchial mucosal hyperemia and edema

and inflammatory cell infiltration in AM and NEU

which was evident in the high dose group (P<0.05). In MYS high and middle-dose groups

cytokines MMP-9

TIMP-1 and TGF-β1 expression levels decreased significantly (P<0.05). Conclusion: MYS may affect the pathological changes of COPD airway remodeling

one of its action mechanisms in intervening COPD airway remodeling may be the down-regulation of excessive MMP-9

TIMP-1 and TGF-β1 expressions

which is most obvious in the high-dose group.