The Preliminary Exploration of What Role miRNAs Derived From Urinary Exosomes Play in Kidney Stone Formation.

OBJECTIVE

To identify dysregulated microRNAs (miRNAs) derived from urinary small Extracellular Vesicles (sEVs) and to explore the potential roles sEVs miRNAs play in nephrolithiasis.

METHODS

First morning voids were collected from participants. Urinary exosomes were isolated via sequential differential centrifugation and ultracentrifugation. Next-generation sequencing was conducted to analyze the transcriptome of urine sEVs from three Calcium oxalate (CaOx) stone patients and three age-/sex-matched healthy controls. Bioinformatics analysis was performed to explore how dysregulated miRNAs were associated with stone formation. The miRNA sequencing results of sEVs derived from epithelial cells (GSE110509) were compared with the dysregulated miRNAs of our study, and finally we found three common miRNAs.

RESULTS

54 dysregulated miRNAs were found between control and stone groups, among which 14 miRNAs were down-regulated and 40 miRNAs were up-regulated in stone groups compared to control groups. Gene ontology (GO) analysis indicated that dysregulated miRNAs were enriched in oxidative stress (Biological Process), focal adhesion (Cellular Component), and cell adhesion molecule binding (Molecular Function). Kyoto Encyclopedia of Genes and Genomes pathways analysis demonstrated that dysregulated miRNAs were common enriched in MAPK signaling pathway, focal adhesion and AGE-RAGE signaling pathway. The expression of miR-223-3p, miR-127-3p, and miR-214-5p were significantly different in either the sEVs derived from cells (GSE110509) or the sEVs derived from urine. QPCR confirmed that the expression of miR-223-3p was higher in urinary sEVs derived from CaOx stone patients.

CONCLUSION

The expression of miR-223-3p is significantly higher in urinary sEVs derived from CaOx stone patients and may affect stone formation via regulating oxidative stress, focal adhesion and inflammation process.