Mechanism of Dahuang Tangluo Pills on Renal Fibrosis in db/db Mice with Diabetic Nephropathy Based on Wnt/β-catenin Pathway

OBJECTIVE To observe the effects of Dahuang Tangluo pills on renal function and fibrosis in db/db mice with diabetic nephropathy, and to explore the possible mechanism based on Wnt/β-catenin pathway.

METHODS  Forty db/db mice were randomly divided into model group, dagliprazin group(1.5 mg·kg⁻¹), and low, medium, high dose groups(0.9, 1.8, 3.6 g·kg⁻¹) of Dahuang Tangluo pills with 8 mice in each group. Another 8 db/m mice were selected as normal group. Normal group and model group were given equal volume normal saline, and 6 groups were given intragastric administration once a day for 10 weeks. Fasting blood glucose(FBG) was measured regularly, urine was collected and microalbumin, urinary creatinine and microalbumin-to-creatinine ratio(ACR) were detected. Cholesterol(CHO) and triglyceride(TG) were detected by automatic biochemical analyzer. The degree of renal fibrosis was observed by Masson staining. Real-Time PCR and Western blotting were used to detect the mRNA and protein expression level of Wnt3a, β-catenin, GSK-3β and p-GSK-3β in kidney. The ultrastructure of kidney cells was observed by transmission electron microscope, and the pathological injury degree of mouse kidney was observed. SPSS 26.0 statistical software was used for data analysis.

RESULTS Compared with normal group, the kidney in model group showed obvious damage and fibrosis, the contents of FBG, CHO, TG and ACR were significantly increased(P<0.01), and the mRNA and protein expression levels of Wnt3a, β-catenin, GSK-3β and p-GSK-3β in kidney tissues were significantly increased(P<0.01). Compared with the model group, the general state and renal tissue ultrastructure damage of mice in each treatment group were improved to varying degrees. The degree of renal fibrosis, FBG, CHO, TG, and ACR were reduced. The mRNA and protein expression levels of Wnt3a, β-catenin, GSK-3β, and p-GSK-3β in renal tissue were also reduced. The high-dose group of Dahuang Tangluo pills had the most significant effect(P<0.01). Effect of Dahuang Tangluo pills on db/db mice with diabetic nephropathy showed a dose-dependent relationship.

CONCLUSION Dahuang Tangluo pills can effectively reduce blood glucose and improve renal fibrosis, the mechanism of which may be related to the inhibition of Wnt/β-catenin pathway.