Alterations of lung microbiota in a mouse model of LPS-induced lung injury
Alterations of lung microbiota in a mouse model of LPS-induced lung injury
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DOI：
10.1152/ajplung.00061.2014
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发表时间：
2015-07-01
影响因子：
4.9
通讯作者：
Birukov, Konstantin G.
中科院分区：
文献类型：
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作者：
Poroyko, Valeriy;Meng, Fanyong;Birukov, Konstantin G.
急性肺损伤（ALI）和更严重的急性呼吸窘迫综合征是对各种感染性和非感染性损伤的常见反应。采用经气管内注射无菌细菌壁脂多糖（LPS）诱导的小鼠急性肺损伤模型，研究小鼠肺内微生物群的变化，以及微生物群落对内毒素损伤引起的肺部炎症和屏障功能障碍的反应。C57BL/6J小鼠气管内注射LPS组（n = 6），无菌水组（n = 7）。治疗后72 h行支气管肺泡灌洗（BAL）。提取细菌DNA，采用qPCR和16S rRNA基因标签（V3-V4）测序（Illumina）。ALI小鼠BAL细菌载量增加了5倍（P = 0.03）。群落复杂性保持不变（Simpson指数，P = 0.7）；Shannon多样性指数表明群落均匀度随ALI的增加而增加（P = 0.07）。主坐标分析和相似性分析（ananosim）检验（P = 0.005）显示，对照组和ALI组之间的微生物群存在显著差异。亚转移试验结果显示，ALI组黄单胞菌科和布鲁氏菌科细菌的丰度增加（P < 0.02）。从两组小鼠肺中均分离到嗜麦芽窄单胞菌（黄单胞菌科）和人类嗜麦芽单胞菌（布鲁氏杆菌科）。BAL的代谢谱检测到适合两种分离物的细菌底物的存在。此外，lps处理小鼠的微生物群加剧了il -6诱导的幼年小鼠肺部炎症。我们得出结论，ALI微生物群的病态转化归因于炎症肺环境中生长的先天性机会性病原体，而不是外部感染因子。
Acute lung injury (ALI) and the more severe acute respiratory distress syndrome are common responses to a variety of infectious and noninfectious insults. We used a mouse model of ALI induced by intratracheal administration of sterile bacterial wall lipopolysaccharide (LPS) to investigate the changes in innate lung microbiota and study microbial community reaction to lung inflammation and barrier dysfunction induced by endotoxin insult. One group of C57BL/6J mice received LPS via intratracheal injection (n = 6), and another received sterile water (n = 7). Bronchoalveolar lavage (BAL) was performed at 72 h after treatment. Bacterial DNA was extracted and used for qPCR and 16S rRNA gene-tag (V3-V4) sequencing (Illumina). The bacterial load in BAL from ALI mice was increased fivefold (P = 0.03). The community complexity remained unchanged (Simpson index, P = 0.7); the Shannon diversity index indicated the increase of community evenness in response to ALI (P = 0.07). Principal coordinate analysis and analysis of similarity (ANOSIM) test (P = 0.005) revealed a significant difference between microbiota of control and ALI groups. Bacteria from families Xanthomonadaceae and Brucellaceae increased their abundance in the ALI group as determined by Metastats test (P < 0.02). In concordance with the 16s-tag data, Stenotrohomonas maltophilia (Xanthomonadaceae) and Ochrobactrum anthropi (Brucellaceae) were isolated from lungs of mice from both groups. Metabolic profiling of BAL detected the presence of bacterial substrates suitable for both isolates. Additionally, microbiota from LPS-treated mice intensified IL-6-induced lung inflammation in naive mice. We conclude that the morbid transformation of ALI microbiota was attributed to the set of inborn opportunistic pathogens thriving in the environment of inflamed lung, rather than the external infectious agents.