Experimental study on the effects of Liuwei Dihuang decoction on MMP-2 and TIMP-2 expression with 5/6 nephrectomized rats

Objective To observe effects of Liuwei Dihuang decoction on the expression of matrix metalloproteinases-2(MMP-2) and tissue inhibitors of metalloproteinases-2(TIMP-2) in remnant kidney of 5/6 nephrectomized rat,and explore the functions of protecting kidney and the mechanism on delaying kidney damage of Liuwei Dihuang decoction.Methods 72 male SD rats were randomly divided into 5 groups as follows: normal group,sham operation group,model group,enalapril group and Liuwei Dihuang decoction group.Rats in model group,enalapril group,Liuwei Dihuang decoction group were established chronic renal failure with 5/6 nephrectomy.Sham operation group rats were operated at the same time but had no damage on kidneys.3 days after the second operation,the rats were treated by gavage.After 8 weeks,rats were sacrificed,remnant kidney tissue morphological changes were observed and MMP-2 and TIMP-2 expression levels were tested by immunohistochemistry.Results(1) Compared with model group,renal tubulointerstitial damage and fibrosis was reduced in Liuwei Dihuang decoction and enalapril group;(2) Compared with model group,MMP-2 expression level was improved and TIMP-2 expression level was reduced markedly in Liuwei Dihuang decoction group(P 0.01).Conclusion Liuwei Dihuang decoction may promote the degradation and decrease the accumulation of extracellular matrix by up-regulating MMP-2 and down-regulating TIMP-2,and then reduce inflammation and fibrosis,thus protecting the kidney function.