PDF(Pubmed)
Abstract：
Renal tubulointerstitial fibrosis (TIF) is considered as the final convergent pathway of diabetic nephropathy (DN) without effective therapies currently. MiRNAs play a key role in fibrotic diseases and become promising therapeutic targets for kidney diseases, while miRNA clusters, formed by the cluster arrangement of miRNAs on chromosomes, can regulate diverse biological functions alone or synergistically. In this study, we developed clustered miR-23a/27a/26a-loaded skeletal muscle satellite cells-derived exosomes (Exos) engineered with RVG peptide, and investigated their therapeutic efficacy in a murine model of DN. Firstly, we showed that miR-23a-3p, miR-26a-5p and miR-27a-3p were markedly decreased in serum samples of DN patients using miRNA sequencing. Meanwhile, we confirmed that miR-23a-3p, miR-26a-5p and miR-27a-3p were primarily located in proximal renal tubules and highly negatively correlated with TIF in db/db mice at 20 weeks of age. We then engineered RVG-miR-23a/27a/26a cluster loaded Exos derived from muscle satellite cells, which not only enhanced the stability of miR-23a/27a/26a cluster, but also efficiently delivered more miR-23a/27a/26a cluster homing to the injured kidney. More importantly, administration of RVG-miR-23a/27a/26a-Exos (100 μg, i.v., once a week for 8 weeks) significantly ameliorated tubular injury and TIF in db/db mice at 20 weeks of age. We revealed that miR-23a/27a/26a-Exos enhanced antifibrotic effects by repressing miRNA cluster-targeting Lpp simultaneously, as well as miR-27a-3p-targeting Zbtb20 and miR-26a-5p-targeting Klhl42, respectively. Knockdown of Lpp by injection of AAV-Lpp-RNAi effectively ameliorated the progression of TIF in DN mice. Taken together, we established a novel kidney-targeting Exo-based delivery system by manipulating the miRNA-23a/27a/26a cluster to ameliorate TIF in DN, thus providing a promising therapeutic strategy for DN.
摘要：
肾小管间质纤维化（TIF）被认为是糖尿病肾病（DN）的最终收敛途径，目前尚无有效的治疗方法。MiRNAs在纤维化疾病中发挥关键作用，并成为肾脏疾病的有希望的治疗靶点。而miRNA簇，由染色体上miRNA的簇排列形成，可以单独或协同调节多种生物学功能。在这项研究中,我们开发了成簇的miR-23a/27a/26a负载的骨骼肌卫星细胞来源的外泌体（Exos），并研究了其在DN小鼠模型中的治疗效果。首先,我们发现miR-23a-3p,使用miRNA测序,miR-26a-5p和miR-27a-3p在DN患者的血清样品中显著降低。同时,我们证实了miR-23a-3p，miR-26a-5p和miR-27a-3p主要位于近端肾小管中,并且在20周龄时与db/db小鼠的TIF高度负相关。然后，我们设计了RVG-miR-23a/27a/26a集群加载来自肌肉卫星细胞的Exos，这不仅增强了miR-23a/27a/26a簇的稳定性，而且还有效地将更多的miR-23a/27a/26a簇归巢到受损的肾脏。更重要的是,施用RVG-miR-23a/27a/26a-Exos（100μg，i.v.,每周一次，持续8周）显着改善了20周龄时db/db小鼠的肾小管损伤和TIF。我们发现miR-23a/27a/26a-Exos通过同时抑制miRNA簇靶向Lpp增强抗纤维化作用,以及miR-27a-3p靶向Zbtb20和miR-26a-5p靶向Klhl42。通过注射AAV-Lpp-RNAi敲除Lpp有效改善DN小鼠中TIF的进展。一起来看,我们通过操纵miRNA-23a/27a/26a簇以改善DN中的TIF，建立了一种新型的肾脏靶向基于Exo的递送系统，从而为DN提供了一种有希望的治疗策略。
