BACKGROUND: Peritoneal fibrosis is a common complication in patients treated with long-term peritoneal dialysis. The aim of this study was to identify the microRNAs (miRNAs) involved in regulation of peritoneal fibrosis in a rat model of peritoneal dialysis. METHODS: Twenty-four Sprague-Dawley (SD) rats were randomly allocated into three groups: (i) Control group (Cg, n = 8); (ii) Saline group (Sg, n = 8): daily intraperitoneal injection with 0.9% normal saline; (iii) Hypertonic dialysate group (HDg, n = 8): daily intraperitoneal injection with 4.25% peritoneal dialysis solution. Rats were sacrificed after four weeks for histological evaluation of peritoneal membrane and the expression of alpha-SMA and COL-1. A miRNA screen was performed using microarray analysis to identify differentially expressed miRNAs, which were then validated by real-time PCR. RESULTS: Compared with the control and the saline groups, hypertonic dialysate group showed impaired peritoneal function accompanied by a spectrum of morphological changes including thicker peritoneal membrane, higher collagen deposition, infiltration of mononuclear cells and neovascularization in the peritoneum. Increased mRNA and protein levels of alpha-SMA and COL-1 were observed in hypertonic dialysate group, indicating the progression of peritoneal fibrosis. The miRNA screen identified 8 significantly down-regulated miRNAs (miR-31, miR-93, miR-100, miR-152, miR-497, miR-192, miR-194 and miR-200b) and one highly up-regulated miRNA (miR-122) in the hypertonic dialysate group. The results were confirmed by real-time PCR. CONCLUSIONS: Altered miRNA expression in peritoneum was found in the rat model of peritoneal fibrosis, indicating that these miRNAs may be associated with pathogenesis of peritoneal fibrosis.
Lin, F., Xu, W., Zhang, H., You, X., Zhang, Z., Shao, R., & Huang, C. (2015). A microrna screen to identify regulators of peritoneal fibrosis in a rat model of peritoneal dialysis. BMC Nephrology, 16(1). https://doi.org/10.1186/s12882-015-0039-z