白细胞介素-10通过降低脂多糖诱导大鼠急性肺损伤高迁移率组蛋白1释放产生保护作用

The protective effect of interleukin-10 on lipopolysaccharide-induced acute lung injury in rats by attenuating the release of extracellular high mobility group protein 1

目的 旨在研究白细胞介素（interleukin,IL）-10对高迁移率组蛋白l（high mobility group protein 1,HMGB1）释放的影响及其肺保护作用,进而探讨IL-10在治疗急性肺损伤中的可能机制. 方法 采用腹腔注射脂多糖（lipopolysaccharide,LPS）致大鼠脓毒症急性肺损伤模型,健康SPF级雄性SD大鼠72只,体重180 g～220 g,采用随机数字表法,随机分为对照组即磷酸盐缓冲液（phosphate buffered solution,PBS）组（P组,6只）、急性肺损伤组即LPS组（L组,30只）、PBS＋IL-10组（PI组,6只）、LPS＋IL-10组（LI组,30只）.P组和PI组腹腔注射等体积PBS的同时分别经由气道滴注5 ml的PBS和IL-10,L组和LI组腹腔注射LPS的同时分别经由气道滴注等体积的PBS和IL-10.L组和LI组注射LPS后的4、8、16、24 h和48 h分别检测各组大鼠肺湿/干重比（wet/dry weight ratio,W/D）和支气管肺泡灌洗液（bronchoalveolar lavage fluid,BALF）中总蛋白浓度,酶联免疫吸附实验法检测BALF中炎性因子肿瘤坏死因子-α（tumor necrosis factor-α,TNF-α）和IL-6水平,苏木精-伊红（hematoxylin-eosin,HE）染色观察肺组织的病理变化,Western Blot分析肺组织中HMGB1表达水平. 结果 腹腔注射LPS后,L组大鼠肺组织W/D和BALF中总蛋白浓度分别为（5.68±0.12） mg/L和（254±105） mg/L,与P组比较,分别增加了12％和297％（P＜0.05）,BALF中TNF-α和IL-6水平明显增加（P＜0.05）,HE染色显示在注射LPS后4h肺组织的细胞浸润达到峰值随后减少,肺组织中HMGB1水平升高（P＜0.05）;使用IL-10后,LI组肺组织W/D和BALF中总蛋白浓度分别为（5.28±0.14） mg/L和（109±48） mg/L,与L组比较,分别降低了7％和57％ （P＜0.05）,BALF中炎性因子水平降低（P＜0.05）,肺组织细胞浸润改善,HMGB1表达下调（P＜0.05）. 结论 IL-10对急性肺损伤具有保护作用,其机制可能为降低BALF中炎性因子的水平,下调晚期炎症介质HMGB1的表达,从而改善肺组织的细胞浸润实现的.

Objective This study aimed to investigate the effect of interleukin （IL）-10 on extracellular release of high mobility group protein 1 （HMGB1） in lipopolysaccharide （LPS）-induced acute lung injury in rats and its possible mechanism.Methods LPS （5 mg/kg,ip） induced acute lung injury model was used in our experiment,the healthy male Sprague-Dawley rats,weighed 180 g-220 g,were randomly divided into four groups：control group only used phosphate buffered solution （PBS） （group P,n=6）,PBS＋IL-10 group （group PI,n=6）,acute lung injury group also LPS group （group L,n=30）,LPS＋interleukin-10 group（group LI,n=30）.In the group L and LI,4,8,16,24 h and 48 h after the injection of LPS,the lung wet/dry weight ratio（W/D） and the concentration of the total protein in bronchoalveolar lavage fluid （BALF） were analyzed.The cytokines [tumor necrosis factor-α（TNF-α） and IL-6] in bronchoalveolar lavage fluid were detected by enzyme-linked immunosorbent assay.Hitophathological changes in lung tissue were observed by hematoxylin-eosin staining,and the expression of HMGB1 was analyzed by Western Blot.Results After using of LPS,the W/D and the concentration of the total protein in BALF in group L were （5.68±0.12） mg/L and （254± 105）mg/L,which were increased by 12% and 297%（P〈0.05）,compared with the group P,the concentration of TNF-α and IL-6 in BALF,HE staining of the lung tissue infiltration and the expression of HMGB1 in the lung tissue were all increased （P〈0.05）.However after the intratracheal spray of IL-10,the W/D and the concentration of the total protein in BALF in group LI were （5.28±0.14） mg/L and （109±48） mg/L,which were decreased by 7% and 57%（P〈0.05）,compared with the group L,the level of inflammatory factors,lung tissue infiltration and the concentration of HMGB1 were all decreased （P＆lt;0.05）.Conclusions IL-10 can attenuate the injury induced by LPS in acute lung injury.The mechanism may be due to the effect of decreasing the proinflammatory cytokines and down-regulating the expression of HMGB1.