Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA.
Department of Urology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Sci Rep. 2018 Jan 19;8(1):1263. doi: 10.1038/s41598-018-19750-y.
To test the hypothesis that intrinsic renal scattered tubular cells (STC-like cells) contribute to repairing injured tubular epithelial cells (TEC) by releasing extracellular vesicle (EV). EV released from primary cultured pig STC-like cells were confirmed by electron microscopy. Antimycin-A (AMA)-induced injured proximal TEC (PK1 cells) were co-cultured with STC-like cells, STC-like cells-derived EV, or EV-free conditioned-medium for 3 days. Cellular injury, oxidative stress and mitochondrial function were assessed. Transfer of mitochondria from STC-like cells to TEC was assessed using Mito-trackers, and their viability by mitochondrial membrane potential assays. STC-like cells-derived EV were intra-arterially injected into mice 2 weeks after induction of unilateral renal artery stenosis. Two weeks later, renal hemodynamics were studied using magnetic-resonance-imaging, and renal fibrosis assessed ex-vivo. Cultured STC-like cells released EV that were uptaken by TEC. A protective effect conferred by STC-like cells in AMA-induced TEC injury was partly mimicked by their EV. Furthermore, STC-like cells-EV carried and transferred mitochondrial material to injured TEC, which partly restored mitochondrial function. In vivo, STC-like cells-derived EV engrafted in the stenotic kidney, and improved its perfusion and oxygenation. STC-like cells-EV exert protective effects on injured tubular cells in vitro and in vivo, partly by transferring STC-like cells mitochondria, which remain at least partly functional in recipient TEC.
为了验证内在肾散射管状细胞（STC 样细胞）通过释放细胞外囊泡（EV）来修复受损管状上皮细胞（TEC）的假设，我们从原代培养的猪 STC 样细胞中证实了 EV 的释放。用抗霉素-A（AMA）诱导的近端 TEC（PK1 细胞）与 STC 样细胞、STC 样细胞衍生的 EV 或无 EV 的条件培养基共培养 3 天，评估细胞损伤、氧化应激和线粒体功能。使用 Mito-tracker 评估 STC 样细胞向 TEC 的线粒体转移，并通过线粒体膜电位测定评估其活力。在单侧肾动脉狭窄诱导后 2 周，将 STC 样细胞衍生的 EV 经动脉内注射入小鼠体内。2 周后，使用磁共振成像研究肾脏血流动力学，并在体外侧评估肾脏纤维化。培养的 STC 样细胞释放的 EV 被 TEC 摄取。STC 样细胞在 AMA 诱导的 TEC 损伤中的保护作用部分被其 EV 模拟。此外，STC 样细胞-EV 携带并转移线粒体物质到受损的 TEC，部分恢复了线粒体功能。在体内，STC 样细胞衍生的 EV 植入狭窄肾脏，并改善其灌注和氧合。STC 样细胞-EV 在体外和体内对受损的管状细胞发挥保护作用，部分是通过转移 STC 样细胞的线粒体，这些线粒体在受者 TEC 中至少部分保持功能。
