Urotensin II Modulates renal interstitial fibrosis in rats

Urotensin-II (UII) is a potent vasoactive peptide, playing an important role in the heart, kidneys and central nervous system. In this study, we investigated the effects of urotensin II on renal fibrosis and its mechanism. The renal interstitial fibrosis model were induced by unilateral ureteral obstruction (UUO) in rats, and the rat renal interstitium fibroblasts (NRK-49F) were used for in vitro mechanism study. Results showed that expression of UII and GPR14 was significantly upregulated at both mRNA and protein levels in the UUO group compared with controls; The pathological features with Masson's trichrome-staining included collagen girdle-shaped in the interstitial of kidney which be ligated; U II exerted the stimulative effect on NRK-49F cell proliferation and DNA synthesis when U at concentrations of 10 -9 and 10 -8mol/L, compared with the Sham group (P<0.01); U II promoted the transdifferentiation of NRK-49F cells by stimulate the expression of the α-SMA and increased the accumulation of ECM, TGF-β1 and CTGF. We concluded that The expression of U II and GPR14 in renal tubular interstitium of UUO rats was increased significantly, and U II may play a crucial role in the progression of kidney fibrosis.