Peng Xiang, Shi Wei, Yu Haitao, Feng Zhenwei, Wei Zongjie, He Weiyang, Gou Xin, Xie Yongpeng
Department of Urology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
Chongqing Key Laboratory of Molecular Oncology and Epigenetics, Chongqing, China.
Front Immunol. 2025 May 30;16:1586174. doi: 10.3389/fimmu.2025.1586174. eCollection 2025.
Ischemia-reperfusion injury (IRI) is a leading contributor to acute kidney injury (AKI), resulting in severe renal dysfunction and increased mortality. Despite progress in medical research, effective therapies for IRI remain limited. Recently, small extracellular vesicles (sEVs) originating from human umbilical cord mesenchymal stem cells (HucMSC-sEVs) have gained attention as potential therapeutic agents for alleviating organ damage. This study aimed to investigate the protective effects of HucMSC-sEVs in renal IRI and explore the underlying mechanisms involved.
HucMSC-sEVs were isolated from HucMSCs via differential ultracentrifugation. Their characteristics were analyzed via transmission electron microscopy (TEM), nanoFCM, and western blotting. The protective effects of HucMSC-sEVs on OGD/R-induced apoptosis in HK-2 cells were evaluated via western blotting and flow cytometric analysis. Additionally, to explore the molecular mechanisms, qRT-PCR, dual-luciferase reporter assays, and other techniques were employed to investigate the role of miR-202-5p in HucMSC-sEVs, with a focus on its ability to regulate the PI3K/AKT pathway through the targeting of GOLIM4. Finally, the therapeutic effects of HucMSC-sEVs were evaluated via a mouse model of IRI.
The HucMSC-sEVs exhibited a characteristic biconcave circular morphology, with a particle size range of 60-100 nm and an average diameter of 79.8 nm. Western blotting confirmed the presence of sEV markers CD9 and TSG101, and HucMSC-sEVs were efficiently taken up by HK-2 cells. In the OGD/R model, HucMSC-sEVs significantly reduced apoptosis, attenuated the expression of BAX and CC3, and promoted the upregulation of BCL-2. Mechanistic studies revealed that HucMSC-sEVs deliver miR-202-5p, which targets GOLIM4 and activates the PI3K/AKT pathway, ultimately reducing renal tubular cell apoptosis. In the mouse IRI model, HucMSC-sEVs significantly alleviated kidney damage and reduced the serum creatinine and urea nitrogen levels.
This study is the first to demonstrate the role of HucMSC-sEVs in attenuating renal IRI both and through the modulation of the GOLIM4/PI3K/AKT pathway via miR-202-5p. These findings identify a novel molecular target for the treatment of AKI via HucMSC-sEVs and provide a strong theoretical basis for their potential clinical application.
缺血再灌注损伤（IRI）是急性肾损伤（AKI）的主要原因，可导致严重的肾功能障碍和死亡率升高。尽管医学研究取得了进展，但针对IRI的有效治疗方法仍然有限。最近，源自人脐带间充质干细胞的小细胞外囊泡（HucMSC-sEVs）作为减轻器官损伤的潜在治疗剂受到关注。本研究旨在探讨HucMSC-sEVs对肾IRI的保护作用，并探索其潜在机制。
通过差速超速离心从人脐带间充质干细胞中分离出HucMSC-sEVs。通过透射电子显微镜（TEM）、纳米流式细胞仪（nanoFCM）和蛋白质印迹法分析其特征。通过蛋白质印迹法和流式细胞术分析评估HucMSC-sEVs对氧糖剥夺/再灌注（OGD/R）诱导的HK-2细胞凋亡的保护作用。此外，为了探索分子机制，采用qRT-PCR、双荧光素酶报告基因测定等技术研究miR-202-5p在HucMSC-sEVs中的作用，重点研究其通过靶向GOLIM4调节PI3K/AKT信号通路的能力。最后，通过IRI小鼠模型评估HucMSC-sEVs的治疗效果。
HucMSC-sEVs呈现出典型的双凹圆形形态，粒径范围为60-100nm，平均直径为79.8nm。蛋白质印迹法证实了sEV标志物CD9和TSG101的存在，并且HK-2细胞有效摄取了HucMSC-sEVs。在OGD/R模型中，HucMSC-sEVs显著减少细胞凋亡，减弱BAX和CC3的表达，并促进BCL-2的上调。机制研究表明，HucMSC-sEVs传递miR-202-5p，其靶向GOLIM4并激活PI3K/AKT信号通路，最终减少肾小管细胞凋亡。在小鼠IRI模型中，HucMSC-sEVs显著减轻肾脏损伤并降低血清肌酐和尿素氮水平。
本研究首次证明了HucMSC-sEVs在减轻肾IRI中的作用，并且通过miR-202-5p调节GOLIM4/PI3K/AKT信号通路发挥作用。这些发现确定了通过HucMSC-sEVs治疗AKI的新分子靶点，并为其潜在的临床应用提供了有力的理论依据。
