【摘要】 为探讨热应激对精原细胞线粒体功能、氧化应激及细胞命运的调控作用,该研究通过体内实验建立小鼠睾丸热应激模型,分析睾丸系数、精子密度与精子运动能力变化;采用苏木素–伊红染色观察生精小管结构改变并计量其直径和面积;透射电镜观察线粒体超微结构;利用睾丸转录组测序筛选差异表达通路;在精原细胞中通过JC-1探针检测线粒体膜电位, DCFH-DA荧光探针检测活性氧水平;实时荧光定量PCR分析脂质代谢基因表达水平;通过EdU和PI荧光染色分别评估细胞增殖与凋亡情况。结果显示,热应激显著降低小鼠睾丸系数、精子密度与精子运动能力,并导致生精小管结构紊乱;转录组分析表明,线粒体功能、TNF响应、代谢过程及氧化应激通路显著富集;睾丸组织透射电镜显示线粒体超微结构损伤,而精原细胞呈现线粒体膜电位下降、网络结构异常及活性氧水平升高,脂质代谢基因ACSL4表达上调而SLC7A11表达下调;细胞增殖活性受到显著抑制,凋亡率显著升高。热应激通过诱导线粒体功能障碍、氧化应激加剧及脂质代谢重编程,进而抑制精原细胞增殖并促进细胞凋亡,其中线粒体功能异常与氧化应激可能是介导热应激生殖损伤的关键早期事件。更多还原

【Abstract】 To investigate the regulatory effects of heat stress on mitochondrial function, oxidative stress, and cell fate in spermatogonia, in vivo experiments were conducted to establish a mouse testicular heat stress model. Testicular coefficient, sperm density, and motility were analyzed. Structural alterations in seminiferous tubules were examined by hematoxylin-eosin staining with measurements of their diameter and area, and mitochondrial ultrastructure was observed by transmission electron microscopy. Additionally, testicular transcriptome sequencing was performed to screen for differentially expressed pathways. In spermatogonia, mitochondrial membrane potential was examined using JC-1 probe, ROS(reactive oxygen species) levels were measured with DCFH-DA fluorescent probe, and lipid metabolism-related gene expression was quantified by real-time PCR. Cell proliferation and apoptosis were assessed by EdU and PI fluorescence staining, respectively. The results demonstrated that heat stress significantly reduced testicular coefficient, sperm density, and motility, and induced disorganization of seminiferous tubules. Transcriptome analysis revealed significant enrichment of pathways related to mitochondrial function, TNF-mediated response, metabolic processes and oxidative stress. TEM(transmission electron microscopy) of testicular tissue revealed ultrastructural damage to mitochondria, while spermatogonia exhibited decreased mitochondrial membrane potential and disruption of the mitochondrial network, with upregulation of lipid metabolism gene ACSL4 and downregulation of SLC7A11. Cell proliferation was significantly inhibited, whereas apoptosis rate was markedly increased. Collectively, heat stress induced mitochondrial dysfunction, an oxidative stress elevation, and lipid metabolic reprogramming, thereby suppressing spermatogonial proliferation and promoting apoptosis. Mitochondrial dysfunction and oxidative stress may represent key early events mediating heat stress-induced reproductive impairment.更多还原