Open-Field Blast Injury Disrupts Corneal Gene Expression Linked to Ion Transport, Sensory Perception, and Neural Signaling.

PURPOSE

Open-field blast injury (OFBI) is a common cause of vision loss. This study investigated OFBI-induced changes in corneal transcriptome, signaling pathways, and protein-protein interactions using RNA sequencing (RNA-seq).

METHODS

Sixty-four C57BL/6J mice were used. OFBI was produced in live mice with 350 g of Composition C4 explosive at a 3 meters (m) standoff distance. RNA was extracted from OFBI-exposed and unexposed corneas, and RNA-seq libraries were generated and sequenced on the Illumina NovaSeq 6000 platform. Reads were aligned to the mouse reference GRCm38 genome using HISAT2. Differential gene expression (DGE) analysis was performed using DESeq2. Pathway enrichments were studied using Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Reactome databases. Protein-protein interaction (PPI) networks were constructed using STRING database and Cytoscape coupled with the cytoHubba plugin.

RESULTS

DGE analysis identified 2860 significantly DGEs in OFBI-exposed mice from unexposed (adjusted P < 0.05) mice. The 30 upregulated and 735 downregulated genes showing a log2 fold change ≥ ±1.5 were identified. Enriched pathways included ion channel and membrane potential regulation, sensory perception, and neurotransmitter signaling. The Grik2, Gabrg3, Drd2, Gabrr1, Gabra2, and Drd4 genes which are commonly associated with ion channel regulation, neuronal signaling, and sensory functions were significantly downregulated on day 14 post-OFBI. The three distinct PPI pathways were associated with ion channels, sensory perception, and neurotransmitter transport. RNA sequence and gene count files are published at the NCBI Gene Expression Omnibus (GSE292886).

CONCLUSIONS

OFBI led to significant disruptions in corneal transcriptome critical in the modulation of ion channel activity, sensory perception, and neurotransmitter signaling.