HuangQi Decoction Ameliorates Renal Fibrosis via TGF-β/Smad Signaling Pathway In Vivo and In Vitro

Objective: Traditional Chinese Medicine compound HuangQi decoction is widely used in clinical treatment of chronic kidney disease, but its role on renal interstitial fibrosis and the underlying mechanism remains unclear. The aim of this study is to investigate the effect of HuangQi decoction on renal interstitial fibrosis and its association with the TGF-beta/Smad signaling pathway. Methods: A total of 120 C57/BL mice were randomly divided into six groups: sham group, sham plus high-dose HuangQi decoction (1.08g/kg) group, unilateral ureteral obstruction ((JUG) model group, and (JUG model plus low to high doses of HuangQi decoction (0.12g /kg, 0.36g/kg and 1.08g/kg respectively) groups. Animals were sacrificed 14 days after the administration and ipsilateral kidney tissue was sampled for pathologic examinations. Immunohistochemistry, PCR and western blot were used to detect the expressions of related molecules in the TGF-beta/Smad signaling pathway. TGF-beta 1 was used in in vitro experiments to induce human kidney proximal tubule epithelial cells (HK2). Results: HuangQi decoction improved ipsilateral kidney fibrosis in (JUG mice and downregulated the expressions of TGF-beta 1, T beta RI, T beta RII, Smad4, Smad2/3, P-Smad2/3, alpha-SMA, collagen type I, III and IV in a dose-dependent manner while upregulated the expression of Smad7 in the same fashion. Similar results were found in in vitro studies. Conclusion: The protective effect of HuangQi decoction for unilateral ureteral obstruction kidney damage in mice was mediated by downregulating the TGF-beta/Smad signaling pathway. 0 2016 The Author(s) Published by S. Karger AG, Basel