茶多酚对哮喘大鼠气道炎症和气道重塑的干预研究

The Effects of Tea Polyphenols on Airway Inflammation and Airway Remodeling in Asthmatic Rats

目的:研究茶多酚(TP)对支气管哮喘大鼠早期和晚期气道氧化应激水平及气道炎症、气道重塑的影响。方法:48只大鼠随机分对照组、哮喘组、早布地奈德(BUD)组、晚BUD组、早TP组和晚TP组,每组8只。早BUD组、早TP组在造模前2周药物干预,晚BUD组、晚TP组在造模5周后药物干预。造模12周时观察各项指标。测定支气管壁的平滑肌面积、胶原沉积面积,以及肺组织转化生长因子-β1(TGF-β1)的表达。测定肺组织TGF-β1含量、丙二醛(MDA)含量及超氧化物歧化酶(SOD)活力。结果:早TP组、晚TP组、早BUD组干预后支气管壁平滑肌面积、胶原沉积面积和TGF-β1含量较哮喘组均有改善(P<0.05或P<0.01)。晚BUD组较哮喘组无明显改善(P>0.05)。哮喘组肺组织中MDA含量明显上升,SOD活性显著下降,与对照组比较差异有统计学意义(P<0.01);各药物干预后SOD活性均上升,MDA含量均下降,以早TP组最明显(P<0.01)。SOD活性与MDA含量呈负相关,TGF-β1含量与MDA含量呈正相关。结论:茶多酚可能通过清除氧自由基,减少气道炎症及氧化应激,从而改善或延缓气道重塑的发生。

Objective： To observe the effects of tea polyphenols （TP） on oxidative stress level, airway inflammation and airway remodeling of early stage and late stage in asthmatic rats. Methods; Forty-eight rats were randomly divided into 6 groups, normal saline group, asthma group, early budesonide （early BUD） group, late BUD group, early TP group and late TP group. Drugs were administrated 2 weeks before sensitizing in early BUD group and early TP group, and administrated 5 weeks after sensitizing in late BUD group and late TP group. The lung tissues were harvested from rats 12 weeks after sensitizing. The smooth muscle area, collagen deposition area and the expression of transforming growth factor-β1 （TGF-β1） were assessed in bronchi and lung tissues. The contents of TGF-β1, malondialdehyde （MDA） and superoxide dismutase （SOD） were also detected. Results： The indicators of airway remodeling were significantly improved in the early TP group, late TP group and early BUD group compared with those in asthma group （P 〈 0.05 or P 〈 0.01）. There was no significant improvement in these indicators between late BUD group and asthma group （P 〉 0.05）. The level of MDA was significantly increased and SOD vitality was significantly decreased in lung tissues of asthma group than those of normal control group （P 〈 0.01）. The 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 was found between TGF-β1 and MDA content. Conclusion： Tea polyphenols intervention could inhibit or delay the formation and development of airway remodeling by controlling the level of oxidative stress and downregnlating airway inflammation in rats.