Abstract: Abstract Objective: To observe the effects of tea polyphenols (TP) on oxidative stress level, airway inflammation and airway remodeling in asthmatic rats of early stage and late stage. Methods :SD rats were sensitized and challenged repeatedly by ovalbumin to establish chronic asthma airway remodeling. 48 rats were randomly divided into 6 groups, a normal saline group, an asthma group, an early budesonide group (early BUD group), a late budesonide group (late BUD group), an early TP group and a late TP group . Drugs were administrated 2 weeks before sensitizing in early BUD group and early TP group, while being administrated 5 weeks after sensitizing in late BUD group and late TP group. The lung tissues were harvested from the rats 12 weeks after sensitizing. Smooth muscle area, collagen deposition area were assessed and the expressions of transforming growth factor--?1（TGF-?1）in bronchi and lung tissues were observed by immunohistochemistry. The contents of TGF-?1 and malondialdehyde (MDA) were tested as well as superoxide dismutase (SOD) vitalities were measured. Results: The indicators of airway remodeling significantly improved in the early TP group, late TP group and early BUD group as compared with those in asthma group（P＜0.01 or P＜0.05), the most obvious in early TP group( all P ＜0.01). No significant differences were found between late BUD group and asthma group (P＞0.05). The asthma group also showed increased MDA content and decreased SOD vitality, both being significantly different from that in normal group (P＜0.01). SOD vitality increased and MDA content decreased in each therapeutic group after intervention. SOD vitality had a negative correlation with MDA content. In addition, a positive correlation between collagen deposition area of bronchial wall and MDA content was also found. Conclusion: Tea polyphenols intervention could inhibit or delay the formation and development of airway remodeling maybe by controlling the level of oxidative stress and downregulating airway inflammation in rats. Early drug intervention by Tea polyphenols or BUD could inhibit airway remodeling. Tea polyphenols may delay airway remodeling better than BUD in late stage in asthmatic rats.

Key words: asthma, airway remodeling, oxidative stress, tea polyphenols