[Effects of simvastatin on TGF-beta system of diabetic rat kidneys].

Objective: To investigate the effects and mechanism of renal benefit of simvastatin on diabetic rat kidneys.

Methods: Twenty STZ-induced SD rats and 10 normal rats were assigned to diabetic rat (DM) group, simvastatin [ 4 mg/( kg x d) ] treatment (S) group and normal control (C) group. Immunohistochemistry, RT-PCR and western-blot were employed to examine the changes of the mRNA and protein expression of TGF-beta1 and Tbeta II R in the kidneys of the rats.

Results: Compared with the normal control group, both the mRNA and protein expression of TGF-beta1 and Tbeta II R in the diabetic rat group and treatment group were significantly increased (P < 0.05). Compared with the diabetic rat group, simvastatin could markedly decrease the mRNA and protein expression of TGF-beta1 and Tbeta II R (P < 0.05).

Conclusion: Simvastatim may play a protective role in the diabetic kidneys by down-regulating TGF-beta1 and Tbeta II R and inhibiting the TGF-beta signal pathway.