SummaryThe process of embryonic development is crucial and radically influences preimplantation embryo competence. It involves oocyte maturation, fertilization, cell division and blastulation and is characterized by different key phases that have major influences on embryo quality. Each stage of the process of preimplantation embryonic development is led by important signalling pathways that include very many regulatory molecules, such as primary and secondary messengers. Many studies, bothin vivoandin vitro, have shown the importance of the contribution of reactive oxygen species (ROS) as important second messengers in embryo development. ROS may originate from embryo metabolism and/or oocyte/embryo surroundings, and their effect on embryonic development is highly variable, depending on the needs of the embryo at each stage of development and on their environment (in vivoor underin vitroculture conditions). Other studies have also shown the deleterious effects of ROS in embryo development, when cellular tissue production overwhelms antioxidant production, leading to oxidative stress. This stress is known to be the cause of many cellular alterations, such as protein, lipid, and DNA damage. Considering that the same ROS level can have a deleterious effect on the fertilizing oocyte or embryo at certain stages, and a positive effect at another stage of the development process, further studies need to be carried out to determine the rate of ROS that benefits the embryo and from what rate it starts to be harmful, this measured at each key phase of embryonic development.

中文翻译：

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繁殖中的活性氧：有害、必需还是两者兼而有之？

摘要胚胎发育过程至关重要，从根本上影响着床前胚胎的能力。它涉及卵母细胞成熟、受精、细胞分裂和囊胚形成，其特点是对胚胎质量有重大影响的不同关键阶段。植入前胚胎发育过程的每个阶段都由重要的信号通路引导，其中包括非常多的调节分子，例如初级和次级信使。许多研究，两者体内和体外，已经表明活性氧（ROS）作为胚胎发育中重要的第二信使的贡献的重要性。ROS可能来源于胚胎代谢和/或卵母细胞/胚胎环境，它们对胚胎发育的影响是高度可变的，这取决于胚胎在每个发育阶段的需求及其环境。体内或以下体外培养条件）。其他研究也显示了 ROS 对胚胎发育的有害影响，当细胞组织产生超过抗氧化剂产生时，会导致氧化应激。众所周知，这种压力是许多细胞改变的原因，例如蛋白质、脂质和 DNA 损伤。考虑到相同的 ROS 水平在某些阶段可能对受精卵母细胞或胚胎产生有害影响，而在发育过程的另一个阶段产生积极影响，需要进一步研究以确定对胚胎有益的 ROS 比率从它开始有害的速度开始，这是在胚胎发育的每个关键阶段进行测量的。