Objective: To study the effects of Qigui Yishen formulae on unilateral ureteral obstruction (UUO) model rats and investigate its mechanism in delaying renal fibrosis progress by regulating the transforming growth factor-β1 (TGF-β1)/Smads/phosphatidylinositol 3 kinase (PI3K) signaling pathway. Method: Thirty two Balb/C mice were used to establish UUO renal disease model

and divided into four groups according to intervention drugs:Qigui Yishen formulae group (Chinese medicine group

10 g·kg-1)

Lotensin group (10 mL·kg-1)

model group and sham-operation group. After experiment

the renal tissues were taken

HE staining and Masson staining were used for pathological detection

and the changes in renal tubular-interstitial index were observed. Immunohistochemistry examination was used to detect the protein expression of TGF-β1

Smads

PI3K and fibronectin (FN). The protein and mRNA expressions of TGF-β1 and PI3K were analyzed by RT-PCR and Western blot. Result: Compared with the sham operation group

renal tubular-interstitial index was significantly increased in model group

and the immunohistochemistry examination results showed that TGF-β1 protein and mRNA expressions

Smads

and FN protein expressions were significantly increased

while PI3K protein expression and mRNA expression were significantly reduced (P<0.05). Compared with the model group

renal tubular-interstitial index was significantly reduced in Chinese medicine group and Lotensin group

and the immunohistochemistry examination results showed that TGF-β1 protein and mRNA expressions

Smads

and FN protein expressions were significantly reduced (P<0.05)

while PI3K protein expression and mRNA expression were significantly increased (P<0.05). Conclusion: Qigui Yishen formulae had treatment effects on delaying renal fibrosis progress in UUO model rats. The mechanism of action might be associated with regulating TGF-β1/Smads/PI3K signaling pathway.