Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital with Nanjing Medical University, Nanjing, Jiangsu, China.
Department of Respiratory and Critical Care Medicine, The Affiliated Jiangning Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.
PeerJ. 2022 Mar 30;10:e13159. doi: 10.7717/peerj.13159. eCollection 2022.
Bronchoalveolar lavage fluid (BALF) exosomes possess different properties in different diseases, which are mediated through microRNAs (miRNAs) and long noncoding RNAs (lncRNAs), among others. By sequencing the differentially expressed lncRNAs in BALF exosomes, we seek potential targets for the diagnosis and treatment of acute lung injury (ALI).
Considering that human and rat genes are about 80% similar, ALI was induced using lipopolysaccharide in six male Wistar rats, with six rats as control (all weighing 200 ± 20 g and aged 6-8 weeks). BALF exosomes were obtained 24 h after ALI. The exosomes in BALF were extracted by ultracentrifugation. The differential expression of BALF exosomal lncRNAs in BALF was analyzed by RNA sequencing. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to predict the functions of differentially expressed lncRNAs, which were confirmed by reverse transcription-polymerase chain reaction.
Compared with the control group, the ALI group displayed a higher wet/dry ratio, tumor necrosis factor-α levels, and interleukin-6 levels (all < 0.001). The airway injection of exosomes in rats led to significant infiltration by neutrophils. A total of 2,958 differentially expressed exosomal lncRNAs were identified, including 2,524 upregulated and 434 downregulated ones. Five lncRNAs confirmed the reliability of the sequencing data. The top three GO functions were phagocytic vesicle membrane, regulation of receptor biosynthesis process, and I-SMAD binding. Salmonella infection, Toll-like receptor signaling pathway, and osteoclast differentiation were the most enriched KEGG pathways. The lncRNA-miRNA interaction network of the five confirmed lncRNAs could be predicted using miRDB.
BALF-derived exosomes play an important role in ALI development and help identify potential therapeutic targets related to ALI.
支气管肺泡灌洗液（BALF）外泌体在不同疾病中具有不同的特性，这些特性是通过 microRNAs（miRNAs）和长链非编码 RNA（lncRNAs）等介导的。通过对 BALF 外泌体中差异表达的 lncRNAs 进行测序，我们寻找急性肺损伤（ALI）诊断和治疗的潜在靶点。
考虑到人类和大鼠的基因约有 80%的相似度，我们使用脂多糖在 6 只雄性 Wistar 大鼠中诱导 ALI，另设 6 只大鼠作为对照（均重 200±20g，年龄 6-8 周）。ALI 后 24h 提取 BALF 外泌体。通过超速离心法提取 BALF 中外泌体。通过 RNA 测序分析 BALF 外泌体中 lncRNAs 的差异表达。GO 和 KEGG 分析预测差异表达 lncRNAs 的功能，并用逆转录-聚合酶链反应进行验证。
与对照组相比，ALI 组的湿/干重比、肿瘤坏死因子-α水平和白细胞介素-6 水平均升高（均<0.001）。气道注射大鼠外泌体后，中性粒细胞明显浸润。共鉴定出 2958 个差异表达的外泌体 lncRNAs，包括 2524 个上调和 434 个下调。5 个 lncRNAs 证实了测序数据的可靠性。GO 功能分析的前 3 个功能是吞噬小体膜、受体生物合成过程的调节和 I-SMAD 结合。最富集的 KEGG 通路有沙门氏菌感染、Toll 样受体信号通路和破骨细胞分化。用 miRDB 可以预测 5 个已确认 lncRNA 的 lncRNA-miRNA 相互作用网络。
BALF 来源的外泌体在 ALI 发展中起重要作用，并有助于确定与 ALI 相关的潜在治疗靶点。
