Department of Orthopedics, Huashan Hospital, Fudan University, Shanghai, 200040, China.
Shanghai Key Laboratory of Molecular Imaging, Shanghai University of Medicine and Health Sciences, Shanghai, 201318, China.
Inflammation. 2020 Aug;43(4):1536-1547. doi: 10.1007/s10753-020-01230-z.
Spinal cord injury (SCI) may lead to severe motor and sensory dysfunction, causing high mortality and disability rates. Adipose tissue-derived mesenchymal stem/stromal cells (ADSCs), especially hypoxia-pretreated ADSCs, represent an effective therapy for SCI by promoting the secretion of exosomes (Exos). Here, we investigated the therapeutic efficacy of exosomes secreted by ADSCs under hypoxia (HExos) and explored potential target molecules. We utilized nanoparticle tracking analysis, electron microscopy, qRT-PCR, and western blotting to analyze differences between HExos and Exos groups. The expression of long noncoding RNAs (lncRNAs) was examined by high-throughput sequencing. The therapeutic effects of different Exos treatments were compared in vitro and in an SCI model in vivo. The interaction between lncRNAs, microRNAs, and mRNA was examined by luciferase reporter experiments. We employed enzyme-linked immunosorbent assay and immunofluorescence to measure inflammatory factor expression and microglial polarization. The results showed that HExos was more effective than Exos for repairing SCI by suppressing inflammatory factor expression, promoting functional recovery, and shifting microglia from M1 to M2 polarization. High-throughput sequencing showed that LncGm37494 expression was significantly higher in HExos than Exos, and its upregulation promoted microglial M1/M2 polarization by inhibiting miR-130b-3p and promoting PPARγ expression, as shown by luciferase reporter experiments. Exos from lncGm37494 overexpressing ADSCs showed a similar therapeutic effect than HExos. The results indicated that HExos repair SCI by delivering lncGm37494, advising that lncGm3749 functions importantly in microenvironmental regulation and shows possibility for SCI treatments.
脊髓损伤 (SCI) 可导致严重的运动和感觉功能障碍，造成高死亡率和残疾率。脂肪组织来源的间充质干细胞/基质细胞 (ADSCs)，特别是缺氧预处理的 ADSCs，通过促进外泌体 (Exos) 的分泌，代表了一种有效的 SCI 治疗方法。在这里，我们研究了缺氧条件下 ADSC 分泌的外泌体 (HExos) 的治疗效果，并探讨了潜在的靶分子。我们利用纳米颗粒跟踪分析、电子显微镜、qRT-PCR 和 Western blot 分析了 HExos 组和 Exos 组之间的差异。通过高通量测序分析长链非编码 RNA (lncRNA) 的表达。在体外和 SCI 模型体内比较了不同 Exos 处理的治疗效果。通过荧光素酶报告实验检测 lncRNA、microRNA 和 mRNA 之间的相互作用。我们采用酶联免疫吸附试验和免疫荧光法测量炎症因子表达和小胶质细胞极化。结果表明，HExos 通过抑制炎症因子表达、促进功能恢复和使小胶质细胞从 M1 向 M2 极化，比 Exos 更有效地修复 SCI。高通量测序显示，HExos 中 LncGm37494 的表达明显高于 Exos，其上调通过抑制 miR-130b-3p 和促进 PPARγ 表达，促进小胶质细胞 M1/M2 极化，如荧光素酶报告实验所示。来自过表达 lncGm37494 的 ADSC 的 Exos 表现出与 HExos 相似的治疗效果。结果表明，HExos 通过递呈 lncGm37494 修复 SCI，提示 lncGm37494 在微环境调节中起重要作用，并为 SCI 治疗提供了可能性。
