Identifying Hub Genes and miRNAs Associated with Mesial Temporal Lobe Epilepsy

Abstract

Objective: Mesial temporal lobe epilepsy (MTLE) is a form of focal epilepsy. Recent studies indicate that microRNAs (miRNAs) are involved in the pathogenesis of MTLE. The purpose of this study was to determine differentially expressed genes (DEGs) and their regulatory miRNAs using bioinformatics analysis. Materials and Methods: The GSE186334 gene expression dataset was retrieved from the Gene Expression Omnibus (GEO) database. DEGs between MTLE and control samples were determined using GEO2R with p<0.05 and |logFC|<−1, |logFC|>1 as the threshold. Metascape was used for functional enrichment and gene ontology (GO) analysis. Protein-protein interactions (PPIs) were generated using the STRING database and visualized with Cytoscape. The top 10 highly connected genes were identified as hub genes. Candidate miRNAs targeting these genes were predicted using the miRDB, miRWalk, TargetScan and miRNet databases. Results: A total of 547 DEGs were found, comprising 380 upregulated and 167 downregulated genes. PPI analysis revealed 10 hub genes: IL6, IL1B, TNF, CCL2, CCL3, CCL4, CXCL8, IL1A, CD86, and CD40LG. miR-15a-5p and the hsa-let-7 family of miRNAs were predicted as potential regulators. Conclusion: Key hub genes and regulatory miRNAs involved in MTLE were identified. The enrichment of proinflammatory genes indicates a significant role of neuroinflammation. miRNAs such as miR-15a-5p and the hsa-let-7 family may critically regulate these pathways. These insights could support the development of new diagnostic biomarkers and therapeutic strategies, pending experimental validation.

Keywords

• miRNAs
• Mesial temporal lobe epilepsy
• DEGs
• Bioinformatics

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