College of Veterinary Medicine, Chungnam National University, Daejeon, Republic of Korea.
Department of Clinical Sciences, College of Veterinary and Animal Sciences, Jhang 35200, Sub-campus University of Veterinary and Animal Sciences, Lahore, Pakistan.
Reprod Domest Anim. 2021 Feb;56(2):342-350. doi: 10.1111/rda.13871. Epub 2020 Dec 19.
Oxidative stress is inevitable as it is derived from the handling, culturing, inherent metabolic activities and medium supplementation of embryos. This study was performed to investigate the protective effect of chitosan nanoparticles (CNPs) on oxidative damage in porcine oocytes. For this purpose, cumulus-oocyte complexes (COCs) derived from porcine slaughterhouse ovaries were exposed to different concentrations of CNPs (0, 10, 25 and 50 µg/ml) during in vitro maturation (IVM). Oocytes treated with 25 µg/ml CNPs showed significantly higher levels of GSH, along with a significant reduction in ROS levels compared to control, CNPs10 and CNPs50 groups. In parthenogenetic embryo production, the maturation rate was significantly higher in the CNPs25 group than that in the control and all other treated groups. In addition, when compared to the CNPs50 and control groups, CNPs25-treated oocytes showed significantly higher cleavage and blastocyst development rates. The highest concentration of CNPs reduced the total cell number and ratio of ICM: TE cells in parthenogenetic embryos, suggesting that there is a threshold where benefits are lost if exceeded. In cloned embryos, the CNPs25 group, as compared to all other treated groups, showed significantly higher maturation and cleavage rates. Furthermore, the blastocyst development rate in the CNPs25-treated group was significantly higher than that in the CNPs50-treated group, as was the total cell number. Moreover, we found that cloned embryos derived from the CNPs25-treated group showed significantly higher expression levels of Pou5f1, Dppa2, and Ndp52il genes, compared with those of the control and other treated groups. Our results demonstrated that 25 µg/ml CNPs treatment during IVM improves the developmental competence of porcine oocytes by reducing oxidative stress.
氧化应激是不可避免的，因为它源自胚胎的处理、培养、固有代谢活动和培养基的补充。本研究旨在探讨壳聚糖纳米粒子（CNPs）对猪卵母细胞氧化损伤的保护作用。为此，从屠宰场猪卵巢中获得的卵丘-卵母细胞复合物（COCs）在体外成熟（IVM）期间暴露于不同浓度的 CNPs（0、10、25 和 50μg/ml）。与对照、CNPs10 和 CNPs50 组相比，用 25μg/ml CNPs 处理的卵母细胞的 GSH 水平显著升高，ROS 水平显著降低。在孤雌胚胎生产中，CNPs25 组的成熟率明显高于对照组和其他处理组。此外，与 CNPs50 和对照组相比，CNPs25 处理的卵母细胞的卵裂和囊胚发育率明显更高。最高浓度的 CNPs 降低了孤雌胚胎的总细胞数和内细胞团：滋养层细胞的比例，这表明存在一个阈值，如果超过这个阈值，益处就会丧失。在克隆胚胎中，与所有其他处理组相比，CNPs25 组的成熟和卵裂率明显更高。此外，CNPs25 处理组的囊胚发育率明显高于 CNPs50 处理组，总细胞数也明显更高。此外，我们发现，与对照组和其他处理组相比，CNPs25 处理组克隆胚胎的 Pou5f1、Dppa2 和 Ndp52il 基因的表达水平明显更高。我们的结果表明，IVM 期间 25μg/ml CNPs 处理可通过降低氧化应激来提高猪卵母细胞的发育能力。
