Hemicastration induced spermatogenesis-related DNA methylation and gene expression changes in mice testis

Hemicastration is unilateral orchiectomy to remove an injured testis, and may influence spermatogenesis. However, the underlying molecular mechanisms are poorly understood. Here, we monitored hemicastrated mice and found no significant difference of growth or testosterone (P > 0.05) compared with control. The genome-wide DNA methylation pattern of remaining testis were investigated by RRBS. Substantial genes harbored differentially methylated regions in gene bodies, and were enriched in process of protein binding and cell adhesion. Moreover, RNA-seq results indicated that 46 DEGs involved in meiotic cell cycle, synaptonemal complex assembly and spermatogenesis were upregulated in the hemicastration group, while 197 DEGs were downregulated, which were related to arachidonic acid metabolism. Integrative analysis revealed that PSMC3IP, which encodes a protein crucial for homologous recombination in spermatocytes, exhibited promoter hypomethylation and higher expression level in hemicastrated mice. Our results demonstrated that hemicastration-induced compensatory response maintained normal growth and fertility in mice. Overall design: A total of four right testis of healthy male KM mice with body maturation were used in this study: two individuals were performed prepubertal hemicastration to remove left testis; At the same time, two counterparts were performed sham surgery.