Transcriptome Analysis in High Temperature Inhibiting Spermatogonial Stem Cell Differentiation In Vitro

As one of the factors of male infertility, high temperature induces apoptosis of differentiated spermatogenic cells, sperm DNA oxidative damage, and changes in morphology and function of Sertoli cells. Spermatogonial stem cells (SSCs) are a type of germline stem cells that maintain spermatogenesis through self-renewal and differentiation. At present, however, the effect of high temperature on SSC differentiation remains unknown. In this study, an in vitro SSC differentiation model was used to investigate the effect of heat stress treatment on SSC differentiation, and RNA sequencing (RNA-seq) was used to enrich the key genes and pathways in high temperature inhibiting SSC differentiation. Results show that 2 days of 37 °C or 43 °C (30 min per day) heat stress treatment significantly inhibited SSC differentiation. The differentiation-related genes c-kit, stra8, Rec8, Sycp3, and Ovol1 were down-regulated after 2 and 4 days of heat stress at 37 °C. The transcriptome of SSCs was significantly differentially expressed on days 2 and 4 after heat stress treatment at 37 °C. In total, 1660 and 7252 differentially expressed genes (DEGs) were identified by RNA-seq in SSCs treated with heat stress at 37 °C for 2 and 4 days, respectively. KEGG pathway analysis showed that p53, ribosome, and carbon metabolism signaling pathways promoting stem cell differentiation were significantly enriched after heat stress treatment at 37 °C. In conclusion, 37 °C significantly inhibited SSC differentiation, and p53, ribosome, and carbon metabolism signaling pathways were involved in this differentiation inhibition process. The results of this study provide a reference for further investigation into the mechanism by which high temperature inhibits SSC differentiation.