Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom.
Centre for Discovery Brain Sciences, Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom.
Physiol Rev. 2023 Oct 1;103(4):2623-2677. doi: 10.1152/physrev.00032.2022. Epub 2023 May 12.
Mammalian eggs (oocytes) are formed during fetal life and establish associations with somatic cells to form primordial follicles that create a store of germ cells (the primordial pool). The size of this pool is influenced by key events during the formation of germ cells and by factors that influence the subsequent activation of follicle growth. These regulatory pathways must ensure that the reserve of oocytes within primordial follicles in humans lasts for up to 50 years, yet only approximately 0.1% will ever be ovulated with the rest undergoing degeneration. This review outlines the mechanisms and regulatory pathways that govern the processes of oocyte and follicle formation and later growth, within the ovarian stroma, through to ovulation with particular reference to human oocytes/follicles. In addition, the effects of aging on female reproductive capacity through changes in oocyte number and quality are emphasized, with both the cellular mechanisms and clinical implications discussed. Finally, the details of current developments in culture systems that support all stages of follicle growth to generate mature oocytes in vitro and emerging prospects for making new oocytes from stem cells are outlined.
哺乳动物的卵子（卵母细胞）是在胎儿期形成的，并与体细胞建立联系形成原始卵泡，从而产生生殖细胞（原始池）的储存。这个池的大小受到生殖细胞形成过程中的关键事件以及影响随后卵泡生长激活的因素的影响。这些调节途径必须确保人类原始卵泡中的卵母细胞储备能够持续长达 50 年，但只有约 0.1%的卵母细胞会被排出，其余的则会退化。本综述概述了卵母细胞和卵泡形成以及随后在卵巢基质中生长的机制和调节途径，直至排卵，并特别参考了人类卵母细胞/卵泡。此外，还强调了衰老通过卵母细胞数量和质量的变化对女性生殖能力的影响，并讨论了细胞机制和临床意义。最后，概述了支持卵泡生长各个阶段的体外培养系统的最新发展，以及从干细胞中产生新卵母细胞的新兴前景。
