Physiology of Reproduction Group, Department of Physiology, Faculty of Veterinary, University of Murcia, 30100 Murcia, Spain.
Institute for Biomedical Research of Murcia, IMIB-Arrixaca, 30100 Murcia, Spain.
Int J Mol Sci. 2022 Dec 18;23(24):16158. doi: 10.3390/ijms232416158.
Controlled ovarian stimulation is a necessary step in some assisted reproductive procedures allowing a higher collection of female gametes. However, consequences of this stimulation for the gamete or the offspring have been shown in several mammals. Most studies used comparisons between oocytes from different donors, which may contribute to different responses. In this work, we use the bovine model in which each animal serves as its own control. DNA methylation profiles were obtained by single-cell whole-genome bisulfite sequencing of oocytes from pre-ovulatory unstimulated follicles compared to oocytes from stimulated follicles. Results show that the global percentage of methylation was similar between groups, but the percentage of methylation was lower for non-stimulated oocytes in the imprinted genes APEG3, MEG3, and MEG9 and higher in TSSC4 when compared to stimulated oocytes. Differences were also found in CGI of imprinted genes: higher methylation was found among non-stimulated oocytes in MEST (PEG1), IGF2R, GNAS (SCG6), KvDMR1 ICR UMD, and IGF2. In another region around IGF2, the methylation percentage was lower for non-stimulated oocytes when compared to stimulated oocytes. Data drawn from this study might help to understand the molecular reasons for the appearance of certain syndromes in assisted reproductive technologies-derived offspring.
控制性卵巢刺激是一些辅助生殖程序中的必要步骤，可以提高女性配子的采集量。然而，这种刺激对配子或后代的影响在几种哺乳动物中已经得到证实。大多数研究使用来自不同供体的卵母细胞进行比较，这可能导致不同的反应。在这项工作中，我们使用牛模型，其中每个动物都作为自己的对照。通过对来自未刺激卵泡的卵母细胞与来自刺激卵泡的卵母细胞进行单细胞全基因组亚硫酸氢盐测序，获得了 DNA 甲基化图谱。结果表明，两组间的总体甲基化百分比相似，但与刺激卵母细胞相比，未刺激卵母细胞在印迹基因 APEG3、MEG3 和 MEG9 中的甲基化百分比较低，而在 TSSC4 中的甲基化百分比较高。印迹基因的 CGI 也存在差异：在 MEST（PEG1）、IGF2R、GNAS（SCG6）、KvDMR1 ICR UMD 和 IGF2 中，未刺激卵母细胞中的甲基化百分比较高。在 IGF2 周围的另一个区域，与刺激卵母细胞相比，未刺激卵母细胞的甲基化百分比较低。本研究得出的数据可能有助于理解辅助生殖技术衍生后代出现某些综合征的分子原因。
