Tello Maria F, Lorenzo María S, Luchetti Carolina G, Maruri Alejandro, Cruzans Paula R, Alvarez Gabriel M, Gambarotta Mariana C, Salamone Daniel F, Cetica Pablo D, Lombardo Daniel M
Universidad de Buenos Aires, Facultad de Ciencias Veterinarias, Instituto de Investigación y Tecnología en Reproducción Animal (INITRA), Cátedra de Histología y Embriología, Buenos Aires, Argentina.
Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina.
Mol Reprod Dev. 2020 Feb;87(2):274-283. doi: 10.1002/mrd.23319. Epub 2020 Jan 26.
The aim of this study was to assess the presence and distribution of apoptosis in porcine cumulus-oocyte complexes (COCs) and its relations with COC morphology and developmental competence. The COCs were obtained from slaughterhouse ovaries, classified into A1 (top category), A2, B1, B2, C, and D based on their morphology. A1, A2, and B1 were matured and fertilized in vitro, and blastocyst rate was compared among them. Before and after in vitro maturation (IVM), annexin-V staining, and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assays were performed to assess early and late apoptosis, respectively. There was a significant increase in both annexin-V (+) oocytes and TUNEL (+) cumulus cells as morphology further deteriorated. There were no statistical differences regarding annexin-V (+) oocytes within immature and post-IVM COCs, but TUNEL (+) oocytes were only observed in post-IVM COCs. Early and late apoptosis was detected in cumulus cells of all categories of immature and post-IVM COCs. However, the difference was only significant for annexin-V (+). There were no significant differences in embryo development. Therefore, apoptosis increases as the morphological features of the immature COCs decrease. In conclusion, the selection of COCs from Categories A1, A2, and B1 may be used as a selection criterion for in vitro development.
本研究的目的是评估猪卵丘-卵母细胞复合体（COCs）中细胞凋亡的存在和分布及其与COC形态和发育能力的关系。COCs取自屠宰场的卵巢，根据其形态分为A1（顶级）、A2、B1、B2、C和D类。将A1、A2和B1类COCs进行体外成熟和受精，并比较它们之间的囊胚率。在体外成熟（IVM）前后，分别进行膜联蛋白-V染色和末端脱氧核苷酸转移酶dUTP缺口末端标记（TUNEL）检测，以评估早期和晚期细胞凋亡。随着形态进一步恶化，膜联蛋白-V（+）卵母细胞和TUNEL（+）卵丘细胞均显著增加。未成熟和IVM后的COCs中膜联蛋白-V（+）卵母细胞无统计学差异，但TUNEL（+）卵母细胞仅在IVM后的COCs中观察到。在所有未成熟和IVM后的COCs类别中，卵丘细胞均检测到早期和晚期细胞凋亡。然而，仅膜联蛋白-V（+）差异显著。胚胎发育无显著差异。因此，随着未成熟COCs形态特征的降低，细胞凋亡增加。总之，从A1、A2和B1类中选择COCs可作为体外发育的选择标准。
