Effect of fluorofenidone on renal interstitial fibrosis in rats with unilateral ureteral obstruction

OBJECTIVE: To investigate the effect of fluorofenidone on renal interstitial fibrosis in rats with unilateral ureteral obstruction (UUO) and to observe the effect of fluorofenidone on the expressions of collagen type I (Col I), collagen type III (Col III), α-smooth muscle actin (α-SMA), connective tissue growth factor (CTGF), platelet derived growth factor (PDGF) in the renal tissues of UUO rats.
 Methods: Male Sprague-Dawley (SD) rats were randomly divided into a sham-operated group, a UUO group, and a flurofenidone group (n=5). UUO model was induced by ligating the left ureter in rats. The rats were treated with 125 mg/(kg.d) fluorofenidone by gastric gavage in the fluorofenidone group at 24 h before the operation, and the rats were treated with the identical dose of 0.5% sodium carboxyl methyl cellulose (CMC-Na) in the other 2 groups. The rats were sacrificed at 14 days after UUO. Pathological changes of the renal tissue were observed by HE and Masson staining, the mRNA expressions of Col I, Col III, α-SMA, PDGF and CTGF were detected by real-time PCR, and the protein expressions of Col I, Col III, PDGF and CTGF were detected by immunohistochemical staining.
 Results: The renal interstitial damage index, relative collagen area and mRNA and protein expressions of Col I and Col III in the renal tissues of the rats in the UUO group significantly increased (P<0.05), and fluorofenidone could reduce these indexes (P<0.05). Compared with the sham-operated group, the protein expressions of α-SMA, PDGF, CTGF and the mRNA expressions of PDGF and CTGF in the renal tissues of the rats in the UUO group were increased, but fluorofenidone could decrease the protein expressions of α-SMA, PDGF, CTGF and the mRNA expressions of PDGF and CTGF (P<0.05).
 Conclusion: Fluorofenidone (125 mg/kg.d) could attenuate renal interstitial fibrosis through inhibition of fibroblast proliferation, myofibroblastic activation, PDGF and CTGF expression.