Ma Xuan, Liu Rongjian, Ren Zhongchang, Qi Yongmei, Wei Dongqiong, Shi Jiamin, Yuan Cong, Huang Dejun
Gansu Key Laboratory of Biomonitoring and Bioremediation for Environmental Pollution, School of Life Sciences, Lanzhou University, Lanzhou 730000, China.
Gansu Key Laboratory of Biomonitoring and Bioremediation for Environmental Pollution, School of Life Sciences, Lanzhou University, Lanzhou 730000, China.
Ecotoxicol Environ Saf. 2025 Sep 1;302:118650. doi: 10.1016/j.ecoenv.2025.118650. Epub 2025 Jul 10.
High temperature (HT) poses a significant threat to aquatic organisms, yet the molecular mechanisms underlying HT-induced reproductive impairment in fish remain unclear. In this study, we demonstrated that both short-term (< 21 days) and long-term (> 120 days) exposure to HT (33℃) induced reproductive dysfunction in male zebrafish, including reduced fertilization rates, impaired sperm quality, inhibited testicular development, and increased offspring mortality. Transcriptome analyses showed that short-term HT exposure primarily disrupted testicular energy metabolism, whereas long-term exposure impaired sperm-egg recognition and binding. By analyzing differentially expressed genes involve in reproductive processes, we detected a significant downregulation of testis-specific serine kinase 6 (tssk6) in zebrafish testis under HT conditions. Notably, injection of tssk6-mRNA partially restored the HT-induced reduction in sperm quality. Further investigation revealed that long-term HT increased DNA methylation in the tssk6 promoter region, thereby inhibiting its expression, suggesting tssk6 as a potential biomarker for reproductive health. These findings establish an epigenetic mechanistic link between environmental HT and reproductive function in aquatic organisms.
高温（HT）对水生生物构成重大威胁，但鱼类中HT诱导生殖损伤的分子机制仍不清楚。在本研究中，我们证明，短期（<21天）和长期（>120天）暴露于高温（33℃）均会导致雄性斑马鱼生殖功能障碍，包括受精率降低、精子质量受损、睾丸发育受抑制以及后代死亡率增加。转录组分析表明，短期HT暴露主要破坏睾丸能量代谢，而长期暴露则损害精卵识别和结合。通过分析参与生殖过程的差异表达基因，我们检测到在HT条件下斑马鱼睾丸中睾丸特异性丝氨酸激酶6（tssk6）显著下调。值得注意的是，注射tssk6 - mRNA可部分恢复HT诱导的精子质量下降。进一步研究表明，长期HT会增加tssk6启动子区域的DNA甲基化，从而抑制其表达，提示tssk6作为生殖健康的潜在生物标志物。这些发现建立了环境HT与水生生物生殖功能之间的表观遗传机制联系。
