Yang Ling, Wang Qingkai, Cui Maosheng, Li Qianjun, Mu Shuqin, Zhao Zimo
College of Life Sciences and Food Engineering, Hebei University of Engineering, Handan 056021, China.
Animal Husbandry and Veterinary Research Institute of Tianjin, Tianjin 300412, China.
Animals (Basel). 2020 Jan 27;10(2):209. doi: 10.3390/ani10020209.
Melatonin treatment can improve quality and in vitro development of porcine oocytes, but the mechanism of improving quality and developmental competence is not fully understood. In this study, porcine cumulus-oocyte complexes were cultured in TCM199 medium with non-treated (control), 10 M luzindole (melatonin receptor antagonist), 10 M melatonin, and melatonin + luzindole during in vitro maturation, and parthenogenetically activated (PA) embryos were treated with nothing (control), or 10 M melatonin. Cumulus oophorus expansion, oocyte survival rate, first polar body extrusion rate, mitochondrial distribution, and intracellular levels of reactive oxygen species (ROS) and glutathione of oocytes, and cleavage rate and blastocyst rate of the PA embryos were assessed. In addition, expression of growth differentiation factor 9 (GDF9), tumor protein p53 (P53), BCL2 associated X protein (BAX), catalase (CAT), and bone morphogenetic protein 15 (BMP15) were analyzed by real-time quantitative PCR. The results revealed that melatonin treatment not only improved the first polar body extrusion rate and cumulus expansion of oocytes via melatonin receptors, but also enhanced the rates of cleavage and blastocyst formation of PA embryos. Additionally, melatonin treatment significantly increased intraooplasmic level of glutathione independently of melatonin receptors. Furthermore, melatonin supplementation not only significantly enhanced mitochondrial distribution and relative abundances of and mRNA, but also decreased intracellular level of ROS and relative abundances of and mRNA of the oocytes. In conclusion, melatonin enhanced the quality and in vitro development of porcine oocytes, which may be related to antioxidant and anti-apoptotic mechanisms.
褪黑素处理可改善猪卵母细胞的质量和体外发育情况，但改善质量和发育能力的机制尚未完全明确。在本研究中，猪卵丘 - 卵母细胞复合体在体外成熟培养期间，分别在未处理（对照）、10 μM 鲁辛朵（褪黑素受体拮抗剂）、10 μM 褪黑素以及褪黑素 + 鲁辛朵的 TCM199 培养基中培养，孤雌激活（PA）胚胎分别不做处理（对照）或用 10 μM 褪黑素处理。评估了卵丘扩展、卵母细胞存活率、第一极体排出率、线粒体分布、卵母细胞内活性氧（ROS）和谷胱甘肽水平，以及 PA 胚胎的分裂率和囊胚率。此外，通过实时定量 PCR 分析了生长分化因子 9（GDF9）、肿瘤蛋白 p53（P53）、BCL2 相关 X 蛋白（BAX）、过氧化氢酶（CAT）和骨形态发生蛋白 15（BMP15）的表达。结果显示，褪黑素处理不仅通过褪黑素受体提高了卵母细胞的第一极体排出率和卵丘扩展，还提高了 PA 胚胎的分裂率和囊胚形成率。此外，褪黑素处理独立于褪黑素受体显著提高了卵母细胞内谷胱甘肽水平。再者，添加褪黑素不仅显著增强了线粒体分布以及 和 mRNA 的相对丰度，还降低了卵母细胞内 ROS 水平以及 和 mRNA 的相对丰度。总之，褪黑素提高了猪卵母细胞的质量和体外发育能力，这可能与抗氧化和抗凋亡机制有关。
