Mesenchymal Stem Cell-Derived Exosomes Attenuate Epithelial–Mesenchymal Transition of HK-2 Cells
Shuai Yin, Shilin Zhou, Dadui Ren, Jing Zhang, Hong Xin, Xiaozhou He, Hongjian Gao, Jiayun Hou, Feng Zeng, Yunjie Lu, Xuemei Zhang, Min Fan
Abstract
Renal fibrosis (RF) predisposes patients to an increased risk of progressive chronic kidney disease, and effective treatments remain elusive. Mesenchymal stem cell (MSC)-derived exosomes are considered a new treatment for tissue damage. Our study aimed to investigate the in vitro effects of bone marrow MSC-derived exosomes (BM-MSC-Exs) on transforming growth factor-β1 (TGF-β1)-induced fibrosis in renal tubular epithelial cells (HK-2 cells) and the associated mechanisms. Herein, we found BM-MSC-Exs could inhibit TGF-β1-induced epithelial–mesenchymal transition (EMT) in HK-2 cells, and may involve autophagy activation of BM-MSC-Exs. Moreover, we first reported that after ceria nanoparticles (CeNPs) treatment, the improvements induced by BM-MSC-Ex on EMT were significantly enhanced by upregulating the expression of Nedd4Lof MSCs and promoting the secretion of exosomes, which contained Nedd4L. In addition, Nedd4L could activate autophagy in HK-2 cells. In conclusion, BM-MSC-Ex prevents the TGF-β1-induced EMT of renal tubular epithelial cells by transporting Nedd4L, which activates autophagy. The results of this in vitro experiment may extend to RF, whereby BM-MSC-Ex may also be used as a novel treatment for improving RF. Renal fibrosis (RF) is an important pathological change in chronic kidney disease that ultimately leads to end-stage renal failure, and effective treatments remain elusive. In this study, there are two contributions. First, our results suggest that bone marrow mesenchymal stem cell-derived exosomes (BM-MSC-Exs) can prevent transforming growth factor-β1 (TGF-β1)-induced epithelial–mesenchymal transition (EMT) of renal tubular epithelial cells through Nedd4L trafficking, which activates autophagy. Second, the improvement effects of BM-MSC-Ex on TGF-β1-induced HK-2 EMT can be enhanced by ceria nanoparticles (CeNPs). The findings in this study may be extended to RF: BM-MSC-Exs may be used as a novel treatment to improve RF.