Analysis of the lncRNA-miRNA-mRNA network to explore the regulation mechanism in human traumatic brain injury.

Traumatic brain injury (TBI) refers to brain dysfunction with or without traumatic structural injury induced by an external force. Nevertheless, the molecular mechanism of TBI remains undefined. Differentially expressed (DE) lncRNAs, DEmRNAs and DEmiRNAs were selected between human TBI tissues and the adjacent histologically normal tissue by high-throughput sequencing. Gene ontology enrichment analysis and Kyoto Encyclopedia of Genes and Genomes pathway analysis of overlapping DEmRNAs between predicted mRNAs of DEmiRNAs and DEmRNAs. The competitive endogenous RNA (ceRNA) network of lncRNA-miRNA-mRNA was established in light of the ceRNA theory. In the ceRNA network, the key lncRNAs were screened out. Then key lncRNAs related ceRNA subnetwork was constructed. After that, qRT-PCR was applied to validate the expression levels of hub genes. 114 DElncRNAs, 1807 DEmRNAs and 6 DEmiRNAs were DE in TBI. The TBI-related ceRNA network was built with 73 lncRNA nodes, 81 mRNA nodes and 6 miRNAs. According to topological analysis, two hub lncRNAs (ENST00000562897 and ENST00000640877) were selected to construct the ceRNA subnetwork. Subsequently, key lncRNA-miRNA-mRNA regulatory axes constructed by two lncRNAs including ENST00000562897 and ENST00000640877, two miRNAs including miR-6721-5p and miR-129-1-3p, two mRNAs including ketohexokinase (KHK) and cyclic nucleotide-gated channel beta1 (CNGB1), were identified. Furthermore, qRT-PCR results displayed that the expression of ENST00000562897, KHK and CNGB1 were significantly decreased in TBI, while the miR-6721-5p expression levels were markedly increased in TBI. The results of our study reveal a new insight into understanding the ceRNA regulation mechanism in TBI and select key lncRNA-miRNA-mRNA axes for prevention and treatment of TBI.