Department of Molecular Endocrinology, National Research Institute for Child Health and Development, Tokyo, Japan.
Front Endocrinol (Lausanne). 2023 Mar 23;14:1160258. doi: 10.3389/fendo.2023.1160258. eCollection 2023.
Ovarian dysfunction is one of the most common features of women with Turner syndrome. In these women, oocyte apoptosis is markedly accelerated from the early stage of fetal life. Reduction in the number of germ cells disturbs primordial follicle development and thereby leads to the formation of streak gonads. There are three possible causes of accelerated germ cell loss in 45,X ovaries. First, chromosomal pairing failure due to X chromosomal aneuploidy is believed to induce meiotic arrest. Indeed, it has been suggested that the dosage of the X chromosome is more critical for the survival of the oocytes than for other cells in the ovary. Second, impaired coupling between oocytes and granulosa cells may also contribute to germ cell apoptosis. Previous studies have shown that 45,X ovaries may tend to lose tight junctions which are essential for intercellular interactions. Lastly, ovarian dysfunction in women with Turner syndrome is partly attributable to the reduced dosage of several genes on the X chromosome. Specifically, , , and some other genes on the X chromosome have been implicated in ovarian function. Further studies on the mechanisms of ovarian dysfunction are necessary to improve the reproductive outcomes of women with Turner syndrome.
卵巢功能障碍是 Turner 综合征女性最常见的特征之一。在这些女性中，卵母细胞凋亡从胎儿期早期就明显加速。生殖细胞数量减少会干扰原始卵泡的发育，从而导致条索状性腺的形成。45,X 卵巢中加速生殖细胞丢失有三个可能的原因。首先，由于 X 染色体非整倍体导致的染色体配对失败，被认为会诱导减数分裂阻滞。事实上，有人认为 X 染色体的剂量对于卵母细胞的存活比对卵巢中的其他细胞更为关键。其次，卵母细胞和颗粒细胞之间的偶联受损也可能导致生殖细胞凋亡。先前的研究表明，45,X 卵巢可能倾向于失去紧密连接，而紧密连接对于细胞间的相互作用是必不可少的。最后，Turner 综合征女性的卵巢功能障碍部分归因于 X 染色体上几个基因的剂量减少。具体而言，X 染色体上的 、 和一些其他基因与卵巢功能有关。需要进一步研究卵巢功能障碍的机制，以改善 Turner 综合征女性的生殖结局。
