Effects of Cordyceps sinensis on expressions of DKK1 and β-catenin in diabetic rats

Objective To stu-dy the effects of Cordyceps sinensis on expression of fibronectin(FN),Dickkopf-1(DKK1) and β-catenin in the kidney of diabetic rats,and to investigate the mechanisms underlying.Methods Diabetes was induced in Wistar rats by intraperitoneal injection of Streptozotocin(60 mg/Kg).Diabetic rats were randomly divided into the none-treatment group(n=12) and the Cordyceps treatment group(n=12).None diabetic Wistar rats were used as controls(n=12).After 12 weeks,the rats were sacrificed.The level of blood glucose,urinary albumin to creatinine ratio(UACR) and creatinine clearance rate(Ccr) were determined.The protein and mRNA levels of DKK1,β-catenin and FN were evaluated by immunohistochemistry and real-time PCR.DKK1 protein expression was further examined by western blot.Results Compared with control group,the levels of UACR and Ccr in no treatment group and Cordyceps treatment group were significantly increased(P0.05),the mRNA and protein levels of FN and DKK1 were significantly elevated(P0.05).Compared to no treatment group,the levels of UACR and Ccr in Cordyceps treatment group were decreased,the mRNA and protein levels of FN and DKK1 were reduced(P0.05).Compared with control group,β-catenin expression was significantly reduced in none-treatment group as demonstrated by immunostaining(P0.05);while β-catenin expression was significantly higher in Cordyceps-treatment group compared with no treatment group(P0.05).Conclusion Cordyceps sinensis may reduce the excessive accumulation of FN in the kidney of diabetic rats through suppressing DKK1 expression and stabilizing β-catenin protein.