支持细胞衍生的外泌体通过旁分泌和自分泌信号调节精原干细胞分化。
Regulation of spermatogonial stem cell differentiation by Sertoli cells-derived exosomes through paracrine and autocrine signaling.
机构信息
Germline Stem Cells and Microenvironment Lab, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China.
Stem Cell Research and Translation Center, Nanjing Agricultural University, Nanjing, China.
出版信息
J Cell Physiol. 2024 Apr;239(4):e31202. doi: 10.1002/jcp.31202. Epub 2024 Jan 30.
In the orchestrated environment of the testicular niche, the equilibrium between self-renewal and differentiation of spermatogonial stem cells (SSCs) is meticulously maintained, ensuring a stable stem cell reserve and robust spermatogenesis. Within this milieu, extracellular vesicles, specifically exosomes, have emerged as critical conveyors of intercellular communication. Despite their recognized significance, the implications of testicular exosomes in modulating SSC fate remain incompletely characterized. Given the fundamental support and regulatory influence of Sertoli cells (SCs) on SSCs, we were compelled to explore the role of SC-derived exosomes (SC-EXOs) in the SSC-testicular niche. Our investigation hinged on the hypothesis that SC-EXOs, secreted by SCs from the testes of 5-day-old mice-a developmental juncture marking the onset of SSC differentiation-participate in the regulation of this process. We discovered that exposure to SC-EXOs resulted in an upsurge of PLZF, MVH, and STRA8 expression in SSC cultures, concomitant with a diminution of ID4 and GFRA1 levels. Intriguingly, obstructing exosomal communication in a SC-SSC coculture system with the exosome inhibitor GW4869 attenuated SSC differentiation, suggesting that SC-EXOs may modulate this process via paracrine signaling. Further scrutiny revealed the presence of miR-493-5p within SC-EXOs, which suppresses Gdnf mRNA in SCs to indirectly restrain SSC differentiation through the modulation of GDNF expression-an indication of autocrine regulation. Collectively, our findings illuminate the complex regulatory schema by which SC-EXOs affect SSC differentiation, offering novel perspectives and laying the groundwork for future preclinical and clinical investigations.
在睾丸龛的协调环境中,精原干细胞(SSC)的自我更新和分化之间的平衡被精心维持,确保了稳定的干细胞储备和强大的精子发生。在这个环境中,细胞外囊泡,特别是外泌体,已经成为细胞间通讯的重要载体。尽管它们的重要性已经得到认可,但睾丸外泌体在调节 SSC 命运方面的作用仍未被完全描述。鉴于支持和调节 SSCs 的 Sertoli 细胞(SCs)的基本作用,我们不得不探索 SC 衍生的外泌体(SC-EXOs)在 SSC-睾丸龛中的作用。我们的研究基于以下假设:SC-EXOs 由来自 5 天大的小鼠睾丸的 SC 分泌,这是 SSC 分化开始的发育节点,参与了这一过程的调节。我们发现,暴露于 SC-EXOs 会导致 SSC 培养物中 PLZF、MVH 和 STRA8 的表达增加,同时 ID4 和 GFRA1 的水平降低。有趣的是,用外泌体抑制剂 GW4869 在 SC-SSC 共培养系统中阻断外泌体通讯会减弱 SSC 的分化,这表明 SC-EXOs 可能通过旁分泌信号来调节这一过程。进一步研究表明,SC-EXOs 中存在 miR-493-5p,它抑制 SC 中的 Gdnf mRNA,通过调节 GDNF 表达间接抑制 SSC 分化,这表明存在自分泌调节。总的来说,我们的发现阐明了 SC-EXOs 影响 SSC 分化的复杂调节模式,为未来的临床前和临床研究提供了新的视角和基础。