Abstract

To investigate the renal protective effect and mechanism of puerarin in diabetic nephropathy rats. In 18 clean grade male Sprague-Dawley rats aged 4 w to 8 w and 12 other male Sprague-Dawley rats in the normal control group, a tail injection of streptozotocin 100 mg/kg was performed to establish the type 2 diabetes mellitus rat model. After successful modeling, rats were randomly divided into model group and puerarin group, with 6 rats in both group. The dosage of puerarin group was 100 mg/kg/d, and the control group and model group were given the same amount of distilled water by gavage for 8 w. The changes of serum creatinine, blood urea nitrogen, total cholesterol, high density lipoprotein cholesterol, triglycerin in rats were detected. The 24 h urinary micro albumin level was measured. The expression of Beclin 1, light chain 3II/light chain 3I and adenosine-monophosphate activated-protein kinase/mammalian target of rapamycin pathway proteins in rat kidney was detected by Western blot. Compared with the control group, the levels of triglycerin and total cholesterol in the model group were raised (p<0.05), and the level of blood lipid in the puerarin group has no difference than that in the model group (p>0.05). The levels of blood urea nitrogen, serum creatinine and urinary micro albumin in the model group were raised than those in the control group (p<0.05), and the level of urinary micro albumin in the puerarin group was reduced than that in the model group (p<0.05), while the other two indicators had no difference compared with the model group. The levels of Beclin 1, light chain 3II/light chain 3I in the renal tissue of the model group were reduced than control group (p<0.05); while the expression levels of Beclin1, light chain 3II/light chain 3I in kidney tissue of rats in puerarin group were raised than model group (p<0.05). The expression of phospho-mammalian target of rapamycin protein in renal tissue of model group was raised than that of control group, while phospho-adenosine monophosphate activated-protein kinase protein was reduced than that of control group (p<0.05). The expression of phosphomammalian target of rapamycin protein in kidney tissue of rats in puerarin group was reduced than that in model group, but phospho-adenosine-monophosphate activated-protein kinase protein was raised than that in model group (p<0.05). Puerarin is helpful to alleviate renal injury induced by diabetes mellitus, and it may be via regulating adenosine-monophosphate activated-protein kinase/mammalian target of rapamycin signal pathway mediated podocyte autophagy.