Department of Obstetrics and Gynecology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, No.600 Yishan Road, Shanghai, 200233, China.
Medical College of Soochow University, Suzhou, 215006, China.
Stem Cell Res Ther. 2020 Jan 3;11(1):3. doi: 10.1186/s13287-019-1508-2.
Premature ovarian failure (POF) has a great impact on reproductive endocrine function in females, and it is an important cause of infertility. Previous studies have demonstrated that small extracellular vesicles (sEVs) derived from stem cells play an important role in tissue regeneration. This study aimed to investigate the therapeutic effect of sEVs derived from embryonic stem cells (ESCs-sEVs) on damaged ovaries and explore the underlying molecular mechanisms.
Mice POF models were established by injecting mice with cyclophosphamide and busulfan. Then, ESCs-sEVs were intravenously transplanted into POF mice. The plasma of mice was harvested at 1 and 2 weeks after treatment to analyze the levels of anti-Mullerian hormone (AMH), estradiol (E), and follicle stimulating hormone (FSH) by ELISA. The morphology of ovaries and follicles was observed by H&E staining, and apoptosis of granulosa cells was detected by TUNEL. In vitro, EdU and CCK-8 tests were used to evaluate the proliferation of cultured granulosa cells stimulated by ESCs-sEVs. Western blotting was used to determine the expression of PI3K/AKT and apoptotic-related proteins.
After transplantation of ESCs-sEVs, the levels of serum sex hormones recovered to normal levels. In addition, the number of follicles was significantly increased, and the number of apoptotic cells was decreased. The results in vitro revealed that ESCs-sEVs could significantly improve the proliferation rate of granulosa cells and increase the expression of phosphorylated PI3K and AKT. Meanwhile, the positive effect on proliferation and the negative effect on apoptosis observed in granulosa cells were obviously decreased when the PI3K/AKT signaling pathway was inhibited.
Our findings suggested that ESCs-sEVs could improve ovarian function by regulating the PI3K/AKT signaling pathway, which could provide a promising clinical therapy for POF.
卵巢早衰（POF）对女性生殖内分泌功能有很大影响，是导致不孕的重要原因。先前的研究表明，来源于干细胞的小细胞外囊泡（sEVs）在组织再生中发挥重要作用。本研究旨在探讨胚胎干细胞来源的 sEVs（ESCs-sEVs）对受损卵巢的治疗作用，并探讨其潜在的分子机制。
通过注射环磷酰胺和白消安建立小鼠 POF 模型，然后将 ESCs-sEVs 静脉移植到 POF 小鼠中。在治疗后 1 周和 2 周采集小鼠血浆，通过 ELISA 分析抗苗勒管激素（AMH）、雌二醇（E）和卵泡刺激素（FSH）的水平。通过 H&E 染色观察卵巢和卵泡的形态，通过 TUNEL 检测颗粒细胞的凋亡。体外实验采用 EdU 和 CCK-8 试验评估 ESCs-sEVs 刺激培养的颗粒细胞的增殖情况。Western blot 用于检测 PI3K/AKT 和凋亡相关蛋白的表达。
移植 ESCs-sEVs 后，血清性激素水平恢复正常。此外，卵泡数量明显增加，凋亡细胞数量减少。体外实验结果表明，ESCs-sEVs 可显著提高颗粒细胞的增殖率，并增加磷酸化 PI3K 和 AKT 的表达。同时，当抑制 PI3K/AKT 信号通路时，观察到对增殖的积极作用和对凋亡的消极作用明显减弱。
我们的研究结果表明，ESCs-sEVs 可通过调节 PI3K/AKT 信号通路改善卵巢功能，为 POF 提供一种有前景的临床治疗方法。
