排卵后衰老是排卵卵母细胞随时间的退化，也是降低后代健康的主要限制因素。这一过程可能会导致卵母细胞凋亡等细胞死亡途径的激活。我们通过 RT-qPCR 评估了卵母细胞膜的完整性、卵子发育能力和凋亡相关基因的 mRNA 丰度。来自斑马鱼斑马鱼的卵母细胞在排卵后 (HPO) 下于 28.5°C 体内保留 24 小时。使用台盼蓝（TB）染色评估活力。体内卵母细胞老化对后代发育能力的影响由受精后 24 小时胚胎存活率、孵化率和幼虫畸形率决定。受精率、卵母细胞活力和孵化率分别为 91%、97% 和 65%。 0 HPO 时，分别下降至 62%、90% 和 4 HPO 时的 22%。 8 HPO 时受精能力降低至 2%，而 72% 的卵母细胞仍具有完整的质膜。凋亡基因 bcl-2（b 细胞淋巴瘤 2）、bada（bcl2 相关细胞死亡激动剂 a）、组织蛋白酶 D、组织蛋白酶 Z、caspase 6a、caspase 7、caspase 8、caspase 9、apaf1、tp53（肿瘤研究发现，在 24 HPO 时，抗凋亡 bcl-2 的 mRNA 丰度降低，促凋亡组织蛋白酶 D 增加。此外，与 0 HPO 相比，24 HPO 时 tp53 和 cdk1 mRNA 转录物减少。因此，TB 染色未检测到因衰老引起的卵母细胞能力丧失。然而，TB 染色可以作为一种简单而快速的方法来评估受精前斑马鱼卵母细胞的质量。总而言之，我们的结果表明斑马鱼卵母细胞衰老晚期细胞死亡途径的激活。版权所有 © 2024 Konar、Mai、Brachs、Waghmare、Samarin、Policar 和 Samarin。

Post-ovulatory aging is a time-dependent deterioration of ovulated oocytes and a major limiting factor reducing the fitness of offspring. This process may lead to the activation of cell death pathways like apoptosis in oocytes.We evaluated oocyte membrane integrity, egg developmental competency, and mRNA abundance of apoptosis-related genes by RT-qPCR. Oocytes from zebrafish Danio rerio were retained in vivo at 28.5°C for 24 h post-ovulation (HPO). Viability was assessed using trypan blue (TB) staining. The consequences of in vivo oocyte aging on the developmental competence of progeny were determined by the embryo survival at 24 h post fertilization, hatching, and larval malformation rates.The fertilization, oocyte viability, and hatching rates were 91, 97, and 65% at 0 HPO and dropped to 62, 90, and 22% at 4 HPO, respectively. The fertilizing ability was reduced to 2% at 8 HPO, while 72% of oocytes had still intact plasma membranes. Among the apoptotic genes bcl-2 (b-cell lymphoma 2), bada (bcl2-associated agonist of cell death a), cathepsin D, cathepsin Z, caspase 6a, caspase 7, caspase 8, caspase 9, apaf1, tp53 (tumor protein p53), cdk1 (cyclin-dependent kinase 1) studied, mRNA abundance of anti-apoptotic bcl-2 decreased and pro-apoptotic cathepsin D increased at 24 HPO. Furthermore, tp53 and cdk1 mRNA transcripts decreased at 24 HPO compared to 0 HPO.Thus, TB staining did not detect the loss of oocyte competency if caused by aging. TB staining, however, could be used as a simple and rapid method to evaluate the quality of zebrafish oocytes before fertilization. Taken together, our results indicate the activation of cell death pathways in the advanced stages of oocyte aging in zebrafish.Copyright © 2024 Konar, Mai, Brachs, Waghmare, Samarin, Policar and Samarin.