Relation between MicroRNA Expression in Peritoneal Dialysis Effluent and Peritoneal Transport Characteristics

BACKGROUND The role of microRNAs (miRNAs) in peritoneal transport is uncertain. METHODS We studied 82 new peritoneal dialysis (PD) patients, 22 prevalent patients without ultrafiltration problem, and 6 patients with documented ultrafiltration problem. Peritoneal transport was determined by standard peritoneal equilibration test (PET). RNA was extracted from the PD effluent after PET, and intra-peritoneal expression of miRNA targets were quantified. RESULTS There were significant difference in the PDE expressions of miR-15a and miR-21. There were modest inverse correlations between ultrafiltration volume and PDE expression of miR-17 (r= -0.198, p =0.041) and miR-377 (r=-0.201, p=0.041). There was an inverse correlations between dialysate-to-plasma creatinine concentration at 4 hours and PDE expression of miR-192 (r=-0.199, p=0.040); while mass transfer area coefficient of creatinine correlated with PDE expression of miR-192 (r=-0.191, p=0.049) and miR-377 (r=0.201, p=0.041). Amongst 7 randomly selected patients who had repeat PET after one year, there was a significant correlation between baseline PDE expression of miR-377 and change in ultrafiltration volume (r=-0.852, p=0.015). CONCLUSION The miRNA expression in PDE, including miR-15a, miR-17, miR-21, miR-30, miR-192, and miR-377, correlated with peritoneal transport characteristics. Our result suggests that miRNA may play a role in the regulation of peritoneal membrane function.