Deciphering testicular aging through whole transcriptome sequencing and ceRNA network analysis in cattle

Male reproductive performance of livestock is widely recognized as a critical economic trait. The testes serve as the core organ of male reproduction, their aging impairs the semen quality and service life of breeding bulls. However, the impact of genes and non-coding RNAs (ncRNAs) on bovine testicular aging remains unclear. In this study, histomorphological and whole transcriptome sequencing analysis was performed on testicular tissues collected from mature (3-year-old) and aged (10-year-old) Wandong cattle. Histological results demonstrated age-related differences in the tubular compartment and interstitial tissue. A total of 3451 differentially expressed genes (DEGs), 2683 lncRNAs (DELs), 100 miRNAs (DEMs), and 348 circRNAs (DECs) were identified. These differentially expressed genes and ncRNAs are enriched in motor proteins, aldosterone synthesis and secretion, and cell cycle pathways. Key DEGs including TNP1/2, PRM1/2, DNAH1, MYO9B, and CASP3/8 were screened. lncRNA/circRNA-mediated competing endogenous RNA (ceRNA) regulatory networks, represented by the let-7/DNAH1 and miR-145/MYO9B axes, were constructed. In summary, this study identified differentially expressed genes and ncRNAs in testicular tissues between mature and aged Wandong bulls, provided novel evidence for deciphering the molecular basis driving testicular aging and spermatogenesis, and offered a theoretical reference for extending the reproductive longevity and improving reproductive performance of breeding bulls.