放射损伤（RI）是接受放射治疗的恶性肿瘤患者中常见的情况。在杀伤肿瘤细胞的同时，靶区周围的正常组织不可避免地受到一定剂量的照射，从而引起不同程度的放射损伤结果。目前，可用于放射损伤的临床治疗方法有限。近年来，干细胞疗法的负面影响被报道得更加清楚，外泌体等非细胞疗法也成为研究人员关注的焦点。作为间充质干细胞（MSC）分泌的一种囊泡样物质，MSC衍生的外泌体（MSC-exo）携带DNA、mRNA、微小RNA（miRNA）、特定蛋白质、脂质和其他参与细胞间信息交换的活性物质。 MSC-exo释放的miRNA能够通过抗细胞凋亡、调节免疫反应、调节炎症反应和促进血管生成等方式减轻和修复受损组织，这表明MSC-exo miRNA在预防和治疗放射损伤方面具有巨大的应用潜力。因此，有必要探讨MSC-exo miRNA在此过程中的潜在治疗机制，这可能为辐射损伤的治疗提供新的思路。越来越多的证据证实，MSC-exo由于抗辐射损伤而在组织修复中显示出令人鼓舞的应用。 - 作为细胞间通讯载体的 miRNA 具有细胞凋亡、免疫反应和促血管生成作用。然而，基于 miRNA 的治疗仍处于起步阶段，临床应用仍有许多实际问题有待解决。

Radiation injury (RI) is a common occurrence in malignant tumors patients receiving radiation therapy. While killing tumor cells, normal tissue surrounding the target area is inevitably irradiated at a certain dose, which can cause varying results of radiation injury. Currently, there are limited clinical treatments available for radiation injuries. In recent years, the negative effects of stem cell therapy have been reported more clearly and non-cellular therapies such as exosomes have become a focus of attention for researchers. As a type of vesicle-like substances secreted by mesenchymal stem cells (MSC), MSC derived exosomes (MSC-exo) carry DNA, mRNA, microRNA (miRNAs), specific proteins, lipids, and other active substances involved in intercellular information exchange. miRNAs released by MSC-exo are capable of alleviating and repairing damaged tissues through anti-apoptosis, modulating immune response, regulating inflammatory response and promoting angiogenesis, which indicates that MSC-exo miRNAs have great potential for application in the prevention and treatment of radiation injury. Therefore, it is necessary to explore the underlying therapeutic mechanisms of MSC-exo miRNAs in this process, which may shed new lights on the treatment of radiation injury.Increasing evidence confirms that MSC-exo has shown encouraging applications in tissue repair due to the anti-apoptotic, immunoreactive, and pro-angiogenesis effects of the miRNAs it carries as intercellular communication carriers. However, miRNA-based therapeutics are still in their infancy and many practical issues remain to be addressed for clinical applications.