Objective: To observe the effects of Fushen Granule on the expression of TAK1 and during renal interstitial fibrosis in rat and explore the possible mechanism. Method :Rat model of renal interstitial fibrosis was produced by unilateral ureter obstruction (UUO). 60 Sprague-Wistar male rats were randomly divided into six groups: sham group (N)

UUO model group (M)

fosinopril group (F0

10 mg ·kg-1 ·d-1)

Fushen Granule group 1 (F1

7.5 g ·kg-1 ·d-1)

Fushen Granule group 2 (F2

15 g ·kg-1 ·d-1) and Fushen Granule group 3 (F3

30 g ·kg-1 ·d-1). All the rats were sacrificed at 14 days after UUO. It was carried out to measure the level of tubulointerstitial damage by HE and Masson staining. The mRNA and protein expression of TAK1 and α-SMA was detected by real-time PCR and Western blot. Result: The renal interstitial fibrotic area and the expression of TAK1 and α-SMA in M group were significantly higher than that in the sham group (P <0.01). In comparison with M group

each intervention group with Fushen Granule or with fosinopril could markedly decreased the expression of TAK1 and α-SMA

especially in Fushen Granule group 2 (P <0.01 or P <0.05). Conclusion:Fushen Granule may downregulate the levels of TAK1 and decrease renal interstitial fibrosis. It is inferred that it may be one of the mechanisms for Fushen Granule to suppress renal tubular damage and interstitial fibrosis.