As renal fibrosis significantly contributes to various kinds of chronic kidney diseases, this study aimed to investigate the renal protective effects of Qingshen Buyang Formula against renal fibrosis on 5/6 nephrectomized rats, and its underlying mechanisms were explored. A total of 24 male Sprague-Dawley rats were randomly divided into sham operation group (Sham group), 5/6 nephrectomy group (5/6Nx group), and Qingshen Buyang Formula treatment group (QBF group). The intervention was intragastric administration for 12 weeks. In the end, the blood samples were collected to test renal functional parameters, urine proteins were measured, and the left kidneys were removed for histological studies, as well as mRNA and protein expression analysis. The results showed that Qingshen Buyang Formula significantly decreased BUN, Scr, and proteinuria in 5/6Nx rats. Meanwhile, it ameliorated the kidney injury and fibrosis, exemplified by the depressed expression of collagen I and fibronectin (FN), which are the main components of ECM. Furthermore, the process of EMT inhibited the Wnt/β-catenin signaling pathway related genes, such as Wnt4, TCF4, β-catenin, and p-GSK3β. Collectively, the Qingshen Buyang Formula can improve renal function and attenuate renal fibrosis, and its underlying mechanisms may be related with inhibiting EMT and Wnt/β-catenin signaling pathway.

The study investigated the expression of Wnt/β-catenin pathway in diabetic rats and the intervention effect of Huayu Tongluo herbs (HTH). Ten rats were randomly selected as control group and the remaining rats were established as diabetic models. The diabetic rats were randomly divided into model group and HTH treatment group. The intervention was intragastric administration in all rats for 20 weeks. At the end of every 4 weeks, fasting blood glucose and 24 h urinary total protein quantitatively were measured. At the end of the 20th week, biochemical parameters and body weight were tested. The kidney tissues were observed under light microscope and transmission electron microscopy. We examined Wnt/beta-catenin signaling pathway key proteins and renal interstitial fibrosis related molecular markers expression. The results showed that HTH could reduce urinary protein excretion and relieve renal pathological damage. Wnt4, p-GSK3β (S9), and β-catenin expression were decreased in the signaling pathway, but GSK3β level was not changed by HTH in diabetic rats. Furthermore, the expressions of TGF-β1 and ILK were decreased, but the level of E-cadherin was increased in diabetic rats after treatment with HTH. This study demonstrated that HTH could inhibit the high expression of Wnt/β-catenin pathway in kidney of diabetic rats. The effect might be one of the main ways to reduce urinary protein excretion.