Department of Reproductive Endocrinology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Department of Obstetrics and Gynaecology, University of British Columbia and British Columbia Children's Hospital Research Institute, Vancouver, British Columbia, Canada.
J Clin Endocrinol Metab. 2018 Jul 1;103(7):2510-2521. doi: 10.1210/jc.2017-02742.
Although glial cell line-derived neurotrophic factor (GDNF) and microRNAs (miRNAs) have been shown to regulate mammalian oocyte maturation, little is known about their effects on human oocyte maturation and the underlying molecular mechanisms.
To examine the effects of GDNF on both nuclear and cytoplasmic maturation in cultured immature human oocytes and to investigate the involvement of miRNAs in GDNF-induced oocyte maturation.
A total of 200 human immature oocytes were used to evaluate the effects of GDNF on oocyte maturation. The involvement of miRNAs in GDNF-induced oocyte maturation was identified by comparing the miRNA expression profiles of cumulus cells (CCs) either with or without GDNF stimulation.
An in vitro fertilization center at the Women's Hospital, Zhejiang University School of Medicine.
Agilent human miRNA (8*60K) arrays were used to examine the miRNA expression patterns of human CCs either with or without GDNF stimulation. miR-145-5p inhibitor and mimic transfections were performed to study downstream gene expression in human CCs.
During the in vitro maturation process, GDNF significantly increased the percentage of metaphase II-stage oocytes and downregulated the expression of miR-145-5p in cultured human CCs. Expression of miR-145-5p in CCs is negatively correlated with oocyte maturation. miR-145-5p mimic significantly decreased the expression of GDNF family receptor-α1, ret proto-oncogene, and epidermal growth factor receptor, whereas miR-145-5p inhibitor reversed these effects. GDNF treatment inhibited cell apoptosis in cultured CCs, and this suppressive effect was reversed by transfection with the miR-145-5p mimic.
Downregulation of miR-145-5p may contribute to GDNF-induced enhancement of oocyte maturation and of cell viability against cell apoptosis.
胶质细胞源性神经营养因子（GDNF）和 microRNAs（miRNAs）已被证明可调节哺乳动物卵母细胞成熟，但关于它们对人卵母细胞成熟的影响及其潜在的分子机制知之甚少。
研究 GDNF 对培养的未成熟人卵母细胞核和细胞质成熟的影响，并探讨 miRNAs 在 GDNF 诱导的卵母细胞成熟中的作用。
共使用 200 个人类未成熟卵母细胞来评估 GDNF 对卵母细胞成熟的影响。通过比较有或没有 GDNF 刺激的卵丘细胞（CCs）的 miRNA 表达谱，确定 miRNAs 在 GDNF 诱导的卵母细胞成熟中的作用。
浙江大学医学院附属妇产科医院体外受精中心。
使用 Agilent 人类 miRNA（8*60K）芯片检测有或没有 GDNF 刺激的人 CCs 的 miRNA 表达模式。进行 miR-145-5p 抑制剂和模拟物转染以研究人 CCs 中的下游基因表达。
在体外成熟过程中，GDNF 显著增加了人 CCs 中 MII 期卵母细胞的百分比，并下调了培养的人 CCs 中 miR-145-5p 的表达。CCs 中 miR-145-5p 的表达与卵母细胞成熟呈负相关。miR-145-5p 模拟物显著降低了 GDNF 家族受体-α1、ret 原癌基因和表皮生长因子受体的表达，而 miR-145-5p 抑制剂则逆转了这些效应。GDNF 处理抑制了培养的 CCs 中的细胞凋亡，而 miR-145-5p 模拟物的转染则逆转了这种抑制作用。
下调 miR-145-5p 可能有助于 GDNF 诱导的卵母细胞成熟增强和细胞活力对抗细胞凋亡。
