Purpose: In this study, we identified differentially expressed genes (DEGs) and signaling pathways to gain insight into the pathogenesis of acute lung injury (ALI). Methods: C57BL/6 mice were intravenously injected with lipopolysaccharide (LPS) to establish a sepsis-induced ALI model. Hematoxylin-eosin (H&E) and enzyme-linked immunosorbent assays (ELISAs) were used to evaluate the model. Whole transcriptome sequencing was performed to identify the expression changes in lncRNAs, circRNAs, miRNAs and mRNAs in lung tissues. The crucial RNAs and the biological function of the target genes were confirmed and annotated based on bioinformatics analysis. Real-time quantitative reverse transcription-polymerase chain reaction (qRT–PCR) was employed to verify the expression levels of key lncRNAs, circRNAs, miRNAs and mRNAs in the lung tissues and human bronchoalveolar lavage (BALF). Results: A total of 3304 (1632 upregulated and 1672 downregulated) differentially expressed mRNAs, 794 (397 up and 397 down) differentially expressed lncRNAs, 89 (58 up and 31 down) differentially expressed circRNAs, and 14 (11 up and 3 down) differentially expressed miRNAs were identified between the control and LPS lung tissues. The lncRNA ceRNA subnetwork and circRNA ceRNA subnetwork were constructed based on the observed interaction and co-expression among the differentially expressed RNAs. An analysis of the protein–protein interaction (PPI) network and hub genes revealed crucial mRNAs for circRNA-Tcf20. The lncRNA-Snhg12, Edn1, Stat1, miR-212-3p and miR-223-3p were upregulated in sepsis ARDS patients. CircRNA-Tcf20, Col1a1, Col1a2 and Flt3 were significantly downregulated in sepsis ARDS patients. The biological function analysis indicated that these genes were enriched in the TNF signaling pathway, Necroptosis signaling pathway and the PI3K-Akt signaling pathway. Conclusions: Our findings suggest that circRNA-Tcf20, miR-212-3p, miR-223-3p, Col1a1, Col1a2 and Flt3 may be new regulatory factors that participate in the pathogenesis of sepsis-related acute lung injury. CircRNA-Tcf20, lncRNA-Snhg12 and all the other RNAs may be potential biomarkers for septic ALI/ARDS.
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