Study on the inhibition effect of the short peptide AcSDKP on renal interstitial fibrosis in rats

Objective To investigate the effect and mechanism of the short peptide acetyl-Ser-Asp-Lys-Pro(AcSDKP) on renal interstitial fibrosis induced by unilateral ureteral obstruction in rats.Methods Thirty-six male Wistar rats were randomly divided into sham-operation group,unilateral ureteral obstruction(UUO) group,and UUO+AcSDKP treatment group.Animal model of rat renal interstitial fibrosis was established by unilateral ureteral ligation.Rats were sacrificed after the surgery for 3 or 14 days.Histological change of the obstructed kidney was observed by H-E staining.The protein expression and localization of transforming growth factor β1(TGF-β1) and a-smooth muscle actin(a-SMA) in renal tissues were detected with immunohistochemical staining.The mRNA levels of TGF-β1 anda-SMA were analyzed with reverse transcription-polymerase chain reaction.Results Compared with sham-operated group,UUO group exhibited severe renal interstitial fibrosis and expressions of TGF-β1 and a-SMA were markedly higher(P 0.05),while renal interstitial fibrosis was less marked and levels of TGF-β1anda-SMA were down-regulated significantly in AcSDKP group(P 0.05).Conclusions AcSDKP improves renal interstitial fibrosis by down-regulating TGF-β1 anda-SMA expression .