Supplementary Material for: Transplantation of Telocytes Attenuates Unilateral Ureter Obstruction-Induced Renal Fibrosis in Rats

<b><i>Background/Aims:</i></b> Previous studies imply that telocytes may have a protective effect on fibrosis in various organs, including the liver, colon, and heart. The effect of telocytes on renal fibrosis remains unknown. Herein, this study was designed to investigate the effect of telocytes on renal fibrosis and the potential mechanisms involved. <b><i>Methods:</i></b> In a unilateral ureteral obstruction (UUO)-induced renal fibrosis model, telocytes were injected via the tail vein every other day for 10 days. The degree of renal damage and fibrosis was determined using histological assessment. The expression of collagen I, fibronectin, epithelial-mesenchymal transition markers, and Smad2/3 phosphorylation was examined by western blot analyses. Real-time PCR and enzyme-linked immunosorbent assay were performed <i>in vivo</i> to detect the levels of transforming growth factor (TGF)-β1 and various growth factors. <b><i>Results:</i></b> Telocytes attenuated renal fibrosis, as evidenced by reduced interstitial collagen accumulation, decreased expression of fibronectin and collagen I, upregulation of E-cadherin, and downregulation of α-smooth muscle actin. Furthermore, telocytes decreased serum TGF-β1 levels, suppressed Smad2/3 phosphorylation, and increased the expression of hepatocyte growth factor (HGF) in rat kidney tissue following UUO. Blockage of HGF counteracted the protective effect of telocytes on UUO-treated kidneys. Through the detection of HGF mRNA levels <i>in vitro</i>, we found that telocytes had no effect on HGF expression compared with renal fibroblasts. <b><i>Conclusion:</i></b> Telocytes attenuated UUO-induced renal fibrosis in rats, likely through enhancing the expression of HGF in an indirect manner.