Oxymatrine inhibits renal fibrosis of obstructive nephropathy by downregulating the TGF-β1-Smad3 pathway.

This study investigated whether oxymatrine (OMT) treatment can ameliorate renal interstitial fibrosis in unilateral ureteral obstruction (UUO) mice model. Moreover, the potential mechanisms of such treatment were analyzed. Twenty-four C57/BL6 mice were randomly divided into three groups, namely sham group, vehicle plus unilateral ureteral obstruction (UUO)-treated group, and 100 mg/kg/d OMT plus UUO-treated group. All mice were euthanized seven days after surgery, and their kidneys were harvested. Renal injury, fibrosis, expression of proinflammatory cytokines, and the transforming growth factor-β1/Smads (TGF-β/Smads) and nuclear factor-kappa B (NF-κB)-signaling pathways were assessed. The results showed OMT significantly prevented kidney injury and fibrosis, as evidenced by decreased expression of collagen-1 and fibronectin. Furthermore, OMT administration inhibited the release of inflammatory factors including tumor necrosis factor-α, (TNF-α) interleukin-1β (IL-1β), and interleukin-6 (IL-6), as well as phosphorylated NF-κB p65. In addition, OMT blocked the activation of myofibroblasts by inhibiting the TGF-β/Smad3-signaling pathway. The findings indicate that OMT-attenuated renal fibrosis and inflammation, and this renoprotective effect may be ascribed to the inactivation of the TGF-β/Smad3 and NF-κB p65 pathways.