Screening of key genes and miRNAs involved in age-related hearing loss

Abstract Background Age-related hearing loss (ARHL) is the most common sensory deficit and refers to the gradual loss of hearing function with age. We aimed to research the differential expression genes during the occur of ARHL and explore microRNAs that maybe regulate these genes. Methods Search the GEO data GSE6045, GSE35234, GSE62173, GSE45026 from NCBI's Gene Expression Omnibus database, and analyze in R. Normalize GEO data by RMA method in R, and use linear microarray data model (LIMMA) method in R to compare young and old mice to find differential genes and microRNAs. Results 109 up-regulated and 121 down-regulated important genes were identified respectively. Functional enrichment shows that they are significantly enriched in protein digestion and absorption, neuroactive ligand-receptor interaction, and PI3K-Akt signaling pathway. Among the top 20 Hub genes, 7 down-regulated genes (Col3a1, Col1a2, Sparc, Col4a2, Col2a1, Lox, Sparc, Ctgf) have verified targeted miRNAs, which have interaction with differential miRNAs of GSE45026. Finally, we designated miR-29a-3p, miR-29b-3p, miR-29c-3p, and miR-124-3p as key miRNAs involved in the development of age-related hearing loss. Conclusions These low expression genes of Col3a1, Col1a2, Sparc, Col4a2, Col2a1,Lox, Sparc, and Ctgf maybe key genes of ARHL, and probably regulated by miR-29a-3p, miR-29b-3p, miR-29c-3p, and miR-124-3p.