Identification and experimental validation of the spinal cord hub genes of aging and neuropathic pain

Pain is considered the most frequent health problem encountered by the elderly. In this study, we used bioinformatics to analyze hub genes related to aging and NP, in order to identify more effective targets for treating NP in older adults. Aging and neuropathic pain (NP) datasets were downloaded from the Gene Expression Omnibus (GEO) database for transcriptome difference analysis. Gene Ontology (GO) functional annotation analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of overlapping genes between aging and NP datasets were made. We constructed the protein-protein interaction (PPI) network based on the STRING database for identification of hub genes, and used the miRDB database to predict the miRNAs that regulated the hub genes. Real-time quantitative polymerase chain reaction (RT-qPCR) analysis was made to verify the expression changes of the hub genes in the spinal cord of aging rats and spared nerve injury (SNI) rats. A total of 56 overlapped differentially expressed genes (DEGs) were identified from GSE18803 and GSE3305 datasets. Eight hub genes were identified by the CytoHubba plugin and MCODE plugin in Cytoscape software, and qPCR confirmed that 6 of them were expressed in the spinal cords of NP and aging rats. Protein tyrosine phosphatase receptor type C (PTPRC), integrin subunit alpha M (ITGAM), CD53, transforming growth factor-β1 (TGFB1), CD68 and CD74 are the hub genes in aging rats and SNI rats.