Exendin-4 ameliorates high glucose-induced fibrosis by inhibiting the secretion of miR-192 from injured renal tubular epithelial cells

Exp Mol Med. 2018 May 1;50(5):1-13. doi: 10.1038/s12276-018-0084-3.

Abstract

Extracellular vesicles (EVs), which contain microRNA (miRNA), constitute a novel means of cell communication that may contribute to the inevitable expansion of renal fibrosis during diabetic kidney disease (DKD). Exendin-4 is effective for treating DKD through its action on GLP1R. However, the effect of exendin-4 on EV miRNA expression and renal cell communication during the development of DKD remains unknown. In this study, we found that EVs derived from HK-2 cells pre-treated with exendin-4 and high glucose (Ex-HG), which were taken up by normal HK-2 cells, resulted in decreased levels of FN and Col-I compared with EVs from HK-2 cells pre-treated with HG alone. Furthermore, we found that pretreatment with HG and exendin-4 may have contributed to a decrease in miR-192 in both HK-2 cells and EVs in a p53-dependent manner. Finally, we demonstrated that the amelioration of renal fibrosis by exendin-4 occurred through a miR-192-GLP1R pathway, indicating a new pathway by which exendin-4 regulates GLP1R. The results of this study suggest that exendin-4 inhibits the transfer of EV miR-192 from HG-induced renal tubular epithelial cells to normal cells, thus inhibiting GLP1R downregulation and protecting renal cells. This study reports a new mechanism by which exendin-4 exerts a protective effect against DKD.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3' Untranslated Regions / genetics
  • Cell Line
  • Down-Regulation
  • Epithelial Cells / metabolism*
  • Epithelial Cells / pathology*
  • Epithelial Cells / ultrastructure
  • Exenatide / pharmacology*
  • Extracellular Vesicles / drug effects
  • Extracellular Vesicles / metabolism
  • Fibrosis
  • Gene Knockdown Techniques
  • Glucagon-Like Peptide-1 Receptor / metabolism
  • Glucose / toxicity*
  • Humans
  • Kidney Tubules / injuries*
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • Models, Biological

Substances

  • 3' Untranslated Regions
  • Glucagon-Like Peptide-1 Receptor
  • MIRN192 microRNA, human
  • MicroRNAs
  • Exenatide
  • Glucose