The protective effect of simvastatin on kidney and its impact on expressions of TLR4 and NF-κB in kidney tissues of type 1 diabetic rats

Objective To evaluate the protective effect of simvastatin on kidney and its impact on expressions of TLR4 and NF-κB in kidney tissues of type 1 diabetic rats.Methods Fifty-four SD rats were divided into normal control,diabetes and simvastatin treated groups.The blood glucose,kidney hypertrophy index and 24 h urinary protein were determined in these groups at 4,8 and 12 weeks,respectively.In addition,the mRNA expressions of TLR4 and NF-κB proteins in the kidney tissues were detected using RT-PCR Fluorescent guantitative PCR(FQ-PCR) and immunohistochemistry,respectively.The changes in ultrastructure of kidney tissues were observed under electron microscope in week 12.Results Compared with the normal control group,the diabetic group had a significant increase in the blood glucose,kidney hypertrophy index and 24 h urine protein excretion(P0.05),and in the mRNA expressions of TLR4 and NF-κB in kidney tissues(P0.05).The glomerular basement membrane was remarkably thickened.In addition,the mesangium and mesenteric cells showed significant proliferation.The simvastatin treated group had a significant decrease in all the data mentioned above(P0.05);nevertheless,the values tended to be higher as compared with the normal control group(P0.05).The pathological findings were also significantly improved,although something different from normal level.Conclusion Simvastatin may protective against early kidney injury in diabetes through down-regulating the expressions of TLR4 and NF-κB,hence inhibition of inflammatory reaction and reduced urine protein.