Abstract:【Abstract】Objective To evaluate the protective effects of the traditional Chinese medicine formula Shenxiankang on renal injury and fibrosis, and to explore its potential mechanisms of action. Methods Chronic kidney disease (CKD) model was established in mice using unilateral ureteral obstruction (UUO). The mice were randomly divided into four groups: sham-operated, model, and Shenxiankang treatment groups with low and high doses (1500, 4500 mg·kg-1·day-1), each comprising eight mice. The intervention groups received daily oral administration of Shenxiankang, and the remaining mice were gavaged equivalent volumes of saline for seven days. After the experiment, renal tissues were collected for assessment of renal injury and fibrosis using H&E and Masson staining. The expression levels of fibrosis markers and proteins involved in the Emp3/TGF-β/Smad3 signaling pathway were determined by Real-time PCR, immunohistochemistry, and western blotting. In cell-based experiments, the effects of Shenxiankang on the Emp3/TGF-β/Smad3 pathway and its interaction with TGFR2 were further analyzed using an Emp3 knockdown and Co-IP assays. Results Shenxiankang significantly reduced immune cell infiltration and tubular atrophy in the UUO model group and decreased the expression of kidney injury markers KIM1 and LCN2, confirming its efficacy in alleviating renal injury. Masson staining and analysis of fibrosis markers (Fibronectin, Fn) and α-SMA indicated that Shenxiankang effectively suppressed fibrosis induced by UUO. Mechanistic studies revealed that Shenxiankang exerted its effects by selectively downregulating the abnormal activation of the Emp3/TGF-β/Smad3 signaling pathway, a finding further supported by cellular experiments showing that Shenxiankang modulates TGF-β/Smad3 signaling through Emp3 regulation. Additionally, Co-IP results demonstrated that Shenxiankang influences the interaction between EMP3 and TGFR2. Conclusions Shenxiankang exhibits significant protective effects in a mouse model of chronic kidney disease, effectively reducing renal injury and fibrosis. These effects are likely mediated through the downregulation of the Emp3/TGF-β/Smad3 signaling pathway, suggesting Shenxiankang’s potential therapeutic value in renal protection.