Integrated study of circRNA, lncRNA, miRNA, and mRNA networks in mediating the effects of testicular heat exposure.

The World Health Organization has recognized that testicular function is temperature dependent. Testicular heat exposure caused by occupational factors, lifestyle, and clinical diseases can lead to different degrees of reproductive problems. The aim of this study was to reveal the transcriptional regulatory network and its potential crucial roles in mediating the effects of testicular heat exposure. Testicular tissue was collected from a group of mice subjected to scrotal heat exposure as well as a control group. RNA was isolated from both groups and used for high-throughput sequencing. Using differential transcriptome expression analysis, 172 circRNAs, 279 miRNAs, 465 lncRNAs, and 2721 mRNAs were identified as significantly differentially expressed in mouse testicular tissue after heat exposure compared with the control group. Through Gene Ontology (GO) term and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses, differentially expressed lncRNAs and mRNAs were found to have potentially important functions in meiotic cell cycle (GO:0051321), cytoplasm (GO:0005737), membrane raft (GO:0045121), MAPK signaling (mmu04010), purine metabolism (mmu00230), and homologous recombination (mmu03440). Some of the most upregulated and downregulated lncRNAs and circRNAs were predicted to be associated with numerous miRNAs and mRNAs through competing endogenous RNA regulatory network analysis, which were validated with molecular biology experiments. This research provides high-throughput sequencing data of a testicular heat exposure model and lays the foundation for further study on circRNAs, miRNAs, and lncRNAs that are involved in male reproductive diseases related to elevated testicular temperature.