脂肪间充质干细胞来源的外泌体介导硬皮病模型小鼠治疗作用的机制研究

Scleroderma is an autoimmune disease characterized by fibrosis of skin and internal organs. Adipose-derived mesenchymal stem cells (ADSCs) derived exosomes (ADSC-Exos) contains a variety of miRNAs, with the functions on promotion of injury repair, it is commonly used in the treatment of a variety of autoimmune diseases. However, there is a lack of research on the treatment of SSc patients with ADSC-Exos. In the present study, it was found that it has therapeutic effect after ADSCs were transplanted into bleomycin-induced murine model of SSc. Accordingly, it was hypothesized that ADSCs could have a therapeutic effect on murine model of SSc by ADSC-Exos. In this study, First, high-throughput sequencing was used to screen miRNAs that were abnormally expressed in murine model of SSc. Secondly, Bioinformatics methods were used to screen miRNAs involved in regulating the Wnt/β-catenin signaling pathway. Finally, we intended to elucidate the mechanism that ADSC-Exos were treated in SSc. This study laid the foundation for the study of pathogenesis and therapeutic mechanism of SSc.

硬皮病（SSc）是以皮肤和内脏器官纤维化为特征的自身免疫性疾病。脂肪间充质干细胞（ADSCs）来源的外泌体（ADSC-Exos）包含多种miRNAs，具有促进损伤修复等功能，因此常用于治疗多种自身免疫性疾病。但是目前缺乏用ADSC-Exos治疗SSc的相关研究。本研究前期发现，将C57BL/6小鼠的ADSCs移植至用博来霉素建立的SSc模型小鼠后，对其有治疗作用。据此提出假设，ADSCs可能通过ADSC-Exos对SSc模型小鼠有治疗作用。本研究首先采用高通量测序法，筛选SSc模型小鼠ADSC-Exos中异常表达的miRNAs。其次，通过生物信息学的方法，筛选出参与Wnt/β-catenin信号通路的miRNAs。最后，通过调节ADSC-Exos中miRNAs的表达，阐明ADSC-Exos可能介导SSc模型小鼠治疗的作用机制。本研究为SSc的发病机理及其治疗机制奠定基础。

项目的背景：本研究以竞争性内源性RNA (Competing endogenous RNA, ceRNA) 理论为基础，通过构建系统性硬化症(systemic sclerosis, SSc)中循环外泌体(Circulating exosome, cirexo) 的lncRNA-miRNA-mRNA网络，分析其作为SSc潜在生物标志物的可能性。探索circular RNA (circRNA) 是否能够通过与真核翻译起始因子4E（eukaryotic translation initiation factor 4E，eIF-4E）结合蛋白1（translation factor eIF4E-binding protein l，4E-BP1）相互作用，介导mTOR信号通路，并参与ceRNA网络，调控系统性硬化症（Systemic Sclerosis，SSc）发生肺纤维化和自噬异常的机制。.重要结果及科学意义：血浆 cirexo中ENST00000313807-hsa-miR-29a-3p-COL1A1互作网络与HRCT、Scl-70、CRP、Ro-52、IL-10、淋巴细胞百分比、中心粒细胞百分比等均具有相关性，经双荧光素酶报告基因检测后发现，ENST00000313807与hsa-miR-29a-3p以及hsa-miR-29a-3p与COL1A1之间存在相互作用。血浆 cirexo中的ENST00000313807-hsa-miR-29a-3p-COL1A1网络可能会成为SSc临床诊断和治疗的潜在生物标志物。在SSc模型小鼠中，可能通过抑制mmu_circ_0005373与4E-BP1蛋白的相互作用促进mTOR信号通路的激活，从而促进Th17细胞的分化，抑制IL-10的表达促进肺纤维化和自噬。预测与mmu_circ_0005373同源的Hsa_circ_0136255也与4E-BP1蛋白相互作用。构建Hsa_circ_0136255/hsa-miR-330-3p/TNFAIP3和hsa_circ_0005373/hsa-miR-892b/TNFAIP3 ceRNA网络。其中，hsa_circ_0136255、hsa_circ_0005373、hsa-miR-330-3p、hsa-miR-892b、TNFAIP3可能作为SSc临床诊断的生物标志物和治疗靶点。