Department of Pediatric Nephrology, the Second Affiliated Hospital of Nanjing Medical University, Nanjing, 210003, China.
Institute of Nephrology, Zhong Da Hospital, Southeast University School of Medicine, Nanjing, 210009, China.
Acta Pharmacol Sin. 2023 Dec;44(12):2455-2468. doi: 10.1038/s41401-023-01140-4. Epub 2023 Aug 18.
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.
肾间质纤维化（TIF）被认为是目前糖尿病肾病（DN）没有有效治疗方法的最终趋同途径。miRNA 在纤维性疾病中发挥关键作用，成为肾脏疾病有前途的治疗靶点，而 miRNA 簇则由染色体上 miRNA 的簇排列形成，可单独或协同调节多种生物学功能。在这项研究中，我们开发了装载有 RVG 肽的聚类 miR-23a/27a/26a 的骨骼肌卫星细胞衍生外泌体（Exos），并在 DN 小鼠模型中研究了它们的治疗效果。首先，我们使用 miRNA 测序显示，DN 患者的血清样本中 miR-23a-3p、miR-26a-5p 和 miR-27a-3p 明显减少。同时，我们证实 miR-23a-3p、miR-26a-5p 和 miR-27a-3p 主要位于近端肾小管中，并且在 20 周龄的 db/db 小鼠中与 TIF 高度负相关。然后，我们设计了装载有肌肉卫星细胞衍生的 miR-23a/27a/26a 簇的 RVG-miR-23a/27a/26a 簇负载的 Exos，不仅增强了 miR-23a/27a/26a 簇的稳定性，而且还能有效地将更多的 miR-23a/27a/26a 簇递送到受损的肾脏。更重要的是，静脉注射 RVG-miR-23a/27a/26a-Exos（100μg，每周一次，共 8 周）可显著改善 20 周龄 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 簇靶向的 Lpp 以及 miR-27a-3p 靶向的 Zbtb20 和 miR-26a-5p 靶向的 Klhl42，增强了抗纤维化作用。注射 AAV-Lpp-RNAi 敲低 Lpp 可有效改善 DN 小鼠 TIF 的进展。总之，我们通过操纵 miRNA-23a/27a/26a 簇建立了一种新型肾脏靶向 Exo 递送系统，以改善 DN 中的 TIF，从而为 DN 提供了一种有前途的治疗策略。
