As an alternative mesenchymal stem cell- (MSC-) based therapy, MSC-derived extracellular vesicles (EVs) have shown promise in the field of regenerative medicine. We previously found that human umbilical cord mesenchymal stem cell-derived EVs (hUCMSC-EVs) improved functional recovery and nerve regeneration in a rat model of sciatic nerve transection. However, the underlying mechanisms are poorly understood. Here, we demonstrated for the first time that hUCMSC-EVs promoted the proliferation of Schwann cells by activating the PI3K/AKT signaling pathway. Furthermore, we showed that hUCMSC-EVs mediated Schwann cell proliferation via transfer of miR-21. Our findings highlight a novel mechanism of hUCMSC-EVs in treating peripheral nerve injury and suggest that hUCMSC-EVs may be an attractive option for clinical application in the treatment of peripheral nerve injury.

中文翻译：

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人脐带间充质干细胞衍生的细胞外囊泡通过转移 miR-21 调节 PI3K/AKT 信号通路促进雪旺氏细胞增殖

作为另一种基于间充质干细胞 (MSC-) 的疗法，MSC 衍生的细胞外囊泡 (EV) 在再生医学领域显示出前景。我们之前发现人脐带间充质干细胞衍生的 EVs（hUCMSC-EVs）改善了坐骨神经横断大鼠模型的功能恢复和神经再生。然而，人们对潜在的机制知之甚少。在这里，我们首次证明 hUCMSC-EVs 通过激活 PI3K/AKT 信号通路促进雪旺氏细胞的增殖。此外，我们发现 hUCMSC-EVs 通过转移 miR-21 介导雪旺氏细胞增殖。