目的 探讨1-羟基-2,3,5-三甲氧基-酮(QGS)对脂多糖(LPS)致小鼠急性肺损伤的保护作用及其机制。方法 采用ipLPS的方法建立小鼠急性肺损伤模型。检测肺脏指数,酶法检测支气管及肺泡灌洗液(BALF)中NO水平,Western blotting法检测核转录因子κB抑制蛋白IκB-α,诱导型一氧化氮合成酶(iNOS)及环氧合酶Ⅱ(COX-2)等蛋白的表达,HE染色观察肺组织病理学改变。结果 QGS500mg/kg组能显著降低LPS引起的小鼠的肺脏指数(P<0.05)。QGS250、500mg/kg组均能显著降低LPS致伤小鼠BALF中NO水平,抑制率分别达到了37%和48.1%。同时QGS500mg/kg组还能够明显增加肺组织中IκB-α蛋白表达量并下调iNOS及COX-2蛋白表达量。结论 QGS对LPS引起的小鼠急性肺损伤有保护作用,该作用与其增加IκB-α蛋白表达而抑制iN-OS和COX-2蛋白的表达有关。

Objective To investigate the protective effects of 1-hydroxy-2, 3, 5-trimethoxyxanthone (QGS) on acute lung injury of mice induced by ip lipopolysaccharide (LPS). Methods Mice were pretreated with QGS for 7 d. Murine models of acute lung injury were duplicated by injection of LPS 20 mg/kg intraperitoneally. In 12 h, the lung weight index was observed and the NO level in the bronchoalveolar lavage fluid (BALF) was measured with kits. The lung was also assessd for the expression of I-κB, inducible nitric oxide synthase (iNOS), and cyclooxygenase-Ⅱ (COX-2) using Western blotting analysis. Lung pathological changes were also observed by HE in each group. Results The lung weight index of injury lung in mice induced by LPS was decreased in 500 mg/kg QGS group (P0.05), the NO level in BALF of mice induced by LPS was decreased significantly in 250 and 500 mg/kg QGS groups with the inhibitory rate of 37% and 48.1%, respectively. Meanwhile the protein expression of IκB-α in lung tissue was increased remarkably but the expression of iNOS and COX-2 was suppressed in 500 mg/kg QGS group. Conclusion QGS could protect mice from the acute lung injury induced by LPS, which is relative to the increasing of IκB-α protein expression and the suppressing of iNOS and COX-2 protein expression.

国家高技术研究发展计划(863计划)(2004AA2Z3783)