Laboratory of Embryonic Metabolism and Epigenetic, Center of Natural and Human Science, Federal University of ABC, Santo Andre, SP, Brazil.
Laboratory of Embryonic Metabolism and Epigenetic, Center of Natural and Human Science, Federal University of ABC, Santo Andre, SP, Brazil; Centre de Recherche en Reproduction, Développement et Santé Intergénérationnelle (CRDSI), Département des Sciences Animales, Faculté des Sciences de l'Agriculture et de l'Alimentation, Université Laval, Quebec, Canada.
Theriogenology. 2021 Oct 1;173:37-47. doi: 10.1016/j.theriogenology.2021.07.010. Epub 2021 Jul 18.
Reproducing the environment to which the embryo is naturally exposed may be an alternative to improve viability of embryos produced in vitro. In the first part of this work, we describe a novel culture media, namely Embryonic Culture Supplementation (ECS100). The composition of this media was based on the contents of carbohydrates and amino acids found in oviductal and uterine fluids. Because it was a new formulation, we investigated the performance of ECS100 in comparison with conventionally used SOFaa, and possible benefits to embryo development. Embryo production rates (cleavage, morula and blastocyst conversion, blastocyst and hatching rates) and morphophysiological parameters (total cell number, cell allocation, Mitochondrial membrane potential (MMP), Reactive Oxygen Species (ROS), NADH, FAD and ATP content) were similar between ECS100 and SOFaa. Next, we tested if a reduction of ECS100 concentration could positively contribute to embryo viability by resembling the more dynamic availability of nutrients that reach the embryos in vivo. Therefore, embryos were cultured in ECS100 or in its serial dilution (ECS75, 50 and 25). Despite the fact that the lowest concentration (ECS25) still supported blastocyst formation, halving the concentration of metabolites (ECS50) actually improved embryo production rates. Thus, embryos produced in ECS100 or ECS50 were submitted to further analyses on Days 4 and 7. Embryos cultured in ECS50 presented better developmental rates and morphophysiological profile than embryos cultured in ECS100. Additionally, physiological traits (MMP, ROS and NADH levels) of embryos cultured in ECS50 presented the expected pattern for embryos produced in vivo. In conclusion, we presented a novel, more personalized and effective culture media for bovine IVP embryos. And although the ECS media formulation was based on the contents of female reproductive fluids, it is worth mentioning that adaptations must be specifically directed for in vitro conditions rather than reproduced exactly from in vivo state.
复制胚胎自然暴露的环境可能是提高体外培养胚胎活力的一种替代方法。在本工作的第一部分，我们描述了一种新型培养基，即胚胎培养补充剂（ECS100）。该培养基的组成基于输卵管和子宫液中发现的碳水化合物和氨基酸含量。由于这是一种新的配方，我们研究了 ECS100 与常规使用的 SOFaa 的性能比较，以及对胚胎发育的可能益处。胚胎产生率（卵裂、桑葚胚和囊胚转换、囊胚和孵化率）和形态生理参数（总细胞数、细胞分配、线粒体膜电位（MMP）、活性氧（ROS）、NADH、FAD 和 ATP 含量）在 ECS100 和 SOFaa 之间相似。接下来，我们测试了降低 ECS100 浓度是否可以通过类似于体内到达胚胎的营养物质的更动态可用性来积极促进胚胎活力。因此，胚胎在 ECS100 或其连续稀释液（ECS75、50 和 25）中培养。尽管最低浓度（ECS25）仍支持囊胚形成，但将代谢物浓度减半（ECS50）实际上提高了胚胎产生率。因此，在 ECS100 或 ECS50 中培养的胚胎在第 4 天和第 7 天进行了进一步分析。在 ECS50 中培养的胚胎显示出比在 ECS100 中培养的胚胎更好的发育率和形态生理特征。此外，在 ECS50 中培养的胚胎的生理特征（MMP、ROS 和 NADH 水平）呈现出与体内产生的胚胎预期的模式。总之，我们提出了一种新型的、更个性化和有效的牛体外受精胚胎培养方法。虽然 ECS 培养基配方是基于雌性生殖液的含量，但值得注意的是，适应必须针对体外条件进行，而不是从体内状态精确复制。
