College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China.
Reproductive Medicine, Guangxi Medical and Health Key Discipline Construction Project, The Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, 533000, China.
Toxicon. 2023 Aug 15;232:107223. doi: 10.1016/j.toxicon.2023.107223. Epub 2023 Jul 10.
Oocyte maturation is important for fertility in mammals, since the quality of oocytes directly affects fertilization, embryo attachment and survival. Nivalenol is widely present in nature as a common toxin that contaminates grain and feed, and it has been reported to cause acute toxicity, immunotoxicity, reproductive toxicity and carcinogenic effects. In this study, we explored the impact of nivalenol on the porcine oocyte maturation and its possible mechanisms. The extrusion of the first polar body was significantly inhibited after incubating oocytes with nivalenol. Meanwhile, nivalenol exposure led to the abnormal distribution of mitochondria, aberrant calcium concentration and the reduction of membrane potential caused a significant decrease in the capacity of mitochondria to generate ATP. In addition, nivalenol induced oxidative stress, and the level of ROS was significantly increased in the nivalenol-treated group, which was confirmed by the perturbation of oxidative stress-related genes. We found that nivalenol-treated oocytes showed positive Annexin-V and γH2A.X signals, indicating the occurrence of apoptosis and DNA damage. In all, our data suggest that nivalenol disrupted porcine oocyte maturation through its effects on mitochondria-related oxidative stress, apoptosis and DNA damage.
卵母细胞成熟对于哺乳动物的生育能力非常重要，因为卵母细胞的质量直接影响受精、胚胎着床和存活。雪腐镰刀菌烯醇作为一种常见的毒素，广泛存在于自然界中，污染谷物和饲料，已被报道具有急性毒性、免疫毒性、生殖毒性和致癌作用。在本研究中，我们探讨了雪腐镰刀菌烯醇对猪卵母细胞成熟的影响及其可能的机制。雪腐镰刀菌烯醇孵育卵母细胞后，第一极体的挤出明显受到抑制。同时，雪腐镰刀菌烯醇暴露导致线粒体分布异常，钙离子浓度异常，膜电位降低，导致线粒体产生 ATP 的能力显著下降。此外，雪腐镰刀菌烯醇诱导氧化应激，雪腐镰刀菌烯醇处理组的 ROS 水平显著升高，这一点通过氧化应激相关基因的扰动得到了证实。我们发现，雪腐镰刀菌烯醇处理的卵母细胞出现阳性的 Annexin-V 和 γH2A.X 信号，表明发生了细胞凋亡和 DNA 损伤。总之，我们的数据表明，雪腐镰刀菌烯醇通过影响与线粒体相关的氧化应激、细胞凋亡和 DNA 损伤来破坏猪卵母细胞的成熟。
