GSDMD基因敲除对内毒素所致小鼠急性肺损伤的保护作用  

Protective effect of GSDMD gene knock-out on acute lung injury induced by LPS in mice

作　　者：帅维正 李军[2] 李大伟[1] 邹剑峰 胡子龙[1] 李琦[1] 李哲[1] 赵哲 张志成[1] Shuai Wei-Zheng;Li Jun;Li Da-Wei;Zou Jian-Feng;Hu Zi-Long;Li Qi;Li Zhe;Zhao Zhe;Zhang Zhi-Cheng(Department of Emergency,the Sixth Medical Center of the Chinese PLA General Hospital,Beijing 100048,China;Department of Medical Administration,the Sixth Medical Center of the Chinese PLA General Hospital,Beijing 100048,China;Outpatient Department of Xinhua News Agency,Beijing 100803,China)

机构地区：[1]解放军总医院第六医学中心重症医学科,北京100048 [2]解放军总医院第六医学中心卫勤部,北京100048 [3]新华通讯社门诊部,北京100803

出　　处：《解放军医学杂志》2020年第11期1125-1130,共6页Medical Journal of Chinese People's Liberation Army

摘　　要：目的探讨GSDMD基因对内毒素所致小鼠急性肺损伤(ALI)的作用。方法20只野生型C57BL/6小鼠和20只GSDMD基因敲除C57BL/6小鼠随机分为野生型对照组(WT-sham组)、野生型ALI组(WT-ALI组)、基因敲除型对照组(KO-sham组)及基因敲除型ALI组(KO-ALI组),每组10只。ALI组经气管滴入1 mg/kg脂多糖(LPS)制备小鼠ALI模型,对照组气管滴入等体积的PBS溶液。造模成功后取肺组织和肺泡灌洗液(BALF)。肺组织行HE染色,光镜下完成肺损伤半定量评分,并测量肺组织湿/干重比(W/D);采用BCA法检测BALF中总蛋白含量,ELISA法检测BALF中TNF-α、IL-1β和IL-6水平;Western blotting检测BALF和肺组织中焦亡相关蛋白的表达。结果与WT-ALI组相比,KO-ALI组小鼠肺损伤半定量评分及肺组织W/D均明显降低(P<0.01),BALF中总蛋白含量以及TNF-α、IL-1β、IL-6水平亦明显降低(P<0.05或P<0.01)。基因敲除型小鼠未见GSDMD蛋白的表达和活化。野生型小鼠和基因敲除小鼠接受LPS处理后,caspase-1和caspase-11蛋白表达均上调(P<0.01)。结论经气管滴入LPS可以诱导小鼠肺内出现GSDMD蛋白的表达和活化,而GSDMD基因敲除有助于降低肺组织炎症水平并减轻肺组织损伤程度。Objective To investigate the potential function of GSDMD in lipopolysaccharide(LPS)induced acute lung injury(ALI)during the inflammatory reaction and lung tissue damage.Methods Twenty wild-type C57BL/6 mice and twenty GSDMD knockout C57BL/6 mice were randomized into the WT-sham group,WT-ALI group,Knockout(KO)-sham group and KOALI group.The ALI was induced by intratracheal injection of LPS(1 mg/kg),using PBS as the treatment control.To examine the inflammatory reaction and tissue damage in the lung,the lung tissue and bronchoalveolar lavage fluid(BALF)were collected.HE staining of lung tissue and the semi-quantitative score of lung injury were performed.The wet/dry ratio of lung tissue and the total protein concentration in BALF were measured by BCA.The levels of TNF-α,IL-1β,and IL-6 in BALF were detected by ELISA.The expression of pyroptosis-related proteins in BALF and lung tissues were detected by Western blotting.Results Compared with the WT-ALI group,the lung injury pathological score,wet/dry ratio,and total protein concentration were all significantly lower in KO-ALI group(P<0.01).Furthermore,the total protein level,TNF-α,IL-1β,and IL-6 levels in BALF were significantly lower in KO-ALI group(P<0.05 or P<0.01).There was no GSDMD and GSDMD-NT expression in the KO mice.After LPS stimulation,the expression levels of caspase-1 and caspase-11 were up-regulated in both wild-type and knockout mice(P<0.01).Conclusions The expression and activation of GSDMD protein in the lung tissue of mice could be induced by intratracheal instillation of LPS and knockout of GSDMD can inhibit the inflammation level of the lung tissue and reduce its damage degree in mice.

关 键 词：急性肺损伤 焦亡 GSDMD 炎症小体 脂多糖 

分 类 号：R363[医药卫生—病理学]