乌司他丁对高氧诱导的新生小鼠肺损伤 模型的疗效研究

Effect of ulinastatin for hyperoxia-induced lung injury in neonatal mice models

目的研究乌司他丁对高氧诱导的新生小鼠肺损伤的疗效,并初步探讨其作用机制。方法新生2日龄昆明小鼠随机分为空气组(46只)及高氧组(46只),分别在空气或55%~65%氧气中饲养至21 d。21 d后空气组随机选取9只作为空气对照组(n=9);高氧组造模成功后再随机分为高氧对照组(n=9),乌司他丁低剂量治疗组(n=9),乌司他丁中剂量治疗组(n=9),乌司他丁高剂量治疗组(n=9),分别给予生理盐水(空气对照组及高氧对照组)、乌司他丁1万U/kg(乌司他丁低剂量治疗组)、5万U/kg(乌司他丁中剂量治疗组)及10万U/kg(乌司他丁高剂量治疗组)腹腔内注射,1次/d,连续用21 d,观察每组小鼠状态及体重变化。21 d后处死各小鼠,观察肺组织外观,HE染色观察肺组织病理结构,免疫组化染色观察肺组织肿瘤坏死因子-α(tumornecrosisfactor-α,TNF-α)表达水平及巨噬细胞浸润的情况;Western印迹法检测肺组织中超氧化物歧化酶(superoxide dismutase,SOD)、丙二醛(malondialehyde,MDA)的活性。统计学方法采用t检验和χ2检验。结果乌司他丁治疗组小鼠体重增长高于高氧对照组,其中乌司他丁高剂量治疗组尤为明显,两组间差异有统计学意义(P<0.05);乌司他丁治疗能显著减轻高氧诱导的肺组织结构紊乱、巨噬细胞浸润、炎性反应及肺水肿,其中乌司他丁高剂量治疗组尤为明显。与高氧对照组比较,乌司他丁治疗组治疗21 d时,肺组织SOD、MDA表达水平变化不大。结论乌司他丁对高氧诱导的新生小鼠肺损伤模型有保护作用,可能主要通过抗炎性反应实现,且其抗炎性作用呈剂量依赖性。

Objective To study the effect of ulinastatin(UTI)for hyperoxia-induced lung injury in neonatal mice,and discuss its mechanism of action preliminarily.Methods Kunming mice at 2 days after birth were randomly divided into air group(46 mice)and hyperoxia group(46 mice),which were fed in air or 55%-65%oxygen for 21 days respectively,9 mice were randomly selected as the air control group(n=9),the high-oxygen group was randomly divided into the high-oxygen control group(n=9),the low-dose UTI treatment group(n=9),the middle-dose UTI treatment group(n=9),and the high-dose UTI treatment group(n=9)after successful modeling.10,000 U/kg,50,000 U/kg and 100000 U/kg of UTI was injected through in abdomen every day to the low-dose UTI treatment group and the middle-dose UTI treatment group and the high-dose UTI treatment group respectively,once per day,21 days in a row,while the air control group and the high-oxygen control group received the same dose of normal saline.Weights and status of rats were recorded.Animals in each group were sacrificed to observe the appearance of lung tissue and calculate the ratio of wet/dry weight of lung tissue.The pathological structure of lung tissue was observed by HE staining,and the expression level of(tumor necrosis factor-α,TNF-α)and the infiltration of macrophages in lung tissue were observed by immuno-histochemical staining.The protein levels of SOD and MDA were assessed using Western blot analysis.Statistical methods were carried out by t-test andχ2 test.Results Body weight of mice in UTI treatment group grew faster than that in the highoxygen control group,especially for the high-dose UTI treatment group,there was statistical significance in two groups(P<0.05).UTI treatment could reduce obviously hyperoxia-induced lung tissue structure disorder macrophage infiltration,inflammatory response and pulmonary edema,attenuated the W/D weight ratio,down-regulated the levels of TNF-αand inhibited macrophage infiltration,especially for the high-dose UTI treatment group.But UTI treatment group had no significant effect on the levels of pulmonary SOD and MDA levels compared with hyperoxic control group at 21 day treatment.Conclusion UTI therapy may be effective in the prevention of hyperoxia-induced lung injury in newborn mice,which may be achieved mainly by anti-inflammatory responses and its anti-inflammatory effects are dose-dependent.