Reproductive Biotechnology in Veterinary, Islamic Azad University, Eqlid Branch, Iran.
Research Institute of Animal Embryo Technology, Shahrekord University, Shahrekord, Iran.
Zygote. 2023 Oct;31(5):411-419. doi: 10.1017/S0967199423000321. Epub 2023 Jun 20.
MicroRNAs (miRNAs) are small non-encoding RNAs that actively regulate biological and physiological processes, and play an important role in regulating gene expression in all cells, especially in most animal cells, including oocytes and embryos. The expression of miRNAs at the right time and place is crucial for the oocyte's maturation and the embryo's subsequent development. Although assisted reproductive techniques (ART) have helped to solve many infertility problems, they cause changes in the expression of miRNA and genes in oocytes and preimplantation embryos, and the effect of these changes on the future of offspring is unknown, and has caused concerns. The relevant genomic alterations commonly imposed on embryos during cryopreservation may have potential epigenetic risks. Understanding the biological functions of miRNAs in frozen maturated oocytes may provide a better understanding of embryonic development and a comparison of fertility conservation in female mammals. With the development of new techniques for genomic evaluation of preimplantation embryos, it has been possible to better understand the effects of ART. The results of various articles have shown that freezing of oocytes and the cryopreservation method are effective for the expression of miRNAs and, in some cases, cause changes in the expression of miRNAs and epigenetic changes in the resulting embryo. This literature review study aimed to investigate the effects of oocyte cryopreservation in both pre-maturation and post-maturation stages, the cryopreservation method and the type of cryoprotectants (CPA) used on the expression of some epigenetic-related genes and miRNAs.
微小 RNA（miRNA）是一种小的非编码 RNA，它能积极调节生物和生理过程，并在调节所有细胞中的基因表达方面发挥重要作用，特别是在大多数动物细胞中，包括卵母细胞和胚胎。miRNA 在正确的时间和位置表达对卵母细胞的成熟和胚胎随后的发育至关重要。虽然辅助生殖技术（ART）已经帮助解决了许多不孕问题，但它们会导致卵母细胞和植入前胚胎中 miRNA 和基因表达的改变，这些改变对后代的未来影响尚不清楚，引起了人们的关注。在冷冻过程中对胚胎施加的相关基因组改变可能存在潜在的表观遗传风险。了解冷冻成熟卵母细胞中 miRNA 的生物学功能可能有助于更好地理解胚胎发育，并比较雌性哺乳动物的生育保存。随着对植入前胚胎进行基因组评估的新技术的发展，人们已经能够更好地了解 ART 的影响。各种文章的结果表明，卵母细胞的冷冻和冷冻方法对 miRNA 的表达是有效的，在某些情况下，会导致 miRNA 的表达变化和由此产生的胚胎中的表观遗传变化。本文献综述研究旨在探讨卵母细胞在预成熟和成熟后阶段的冷冻、冷冻方法以及使用的不同类型的冷冻保护剂（CPA）对一些与表观遗传相关的基因和 miRNA 表达的影响。
