Abstract: Objective To explore the kidney protecting effect and possible mechanism under which the renal tissues in 5/6 nephrectomy rats was intervened by emodin-polylactic-co-glycolic acid nanoparticles. Methods Rats were randomly divided into two groups, eight as Sham-operated group and twenty-four as model group. After rats model was successfully established, twenty-four rats in model group were randomly and equally assigned into Model group (Model group), emodin group eight(EMD)and nanoparticles group eihgt (NPs). Drugs were given to rats in different groups for a total 8 weeks, then 24h urine protein, blood urea nitrogen (BUN)and creatinine (SCr) were measured by their corresponding methods respectively; kidney pathological changes was observed under optical microscope; protein and mRNA expression of growth factor beta-1(TGF-β1) as well as connective tissue growth factor (CTGF) in renal tissues were detected respectively by RT-PCR methods and immunohistochemistry. Results After treated with drugs,compared with sham group,24h urine protein,blood urea nitrogen, serum creatinine, mRNA and protein expression of TGF-β1 and CTGF of rats in model group were both increased(P<0.01);Compared with model group,24h urine protein,blood urea nitrogen,serum creatinine, mRNA and protein expression of TGF-β1 and CTGF of rats in EMD group and NPs group were both decreased(P<0.01);Compared with EMD group,24h urine protein,blood urea nitrogen,serum creatinine, mRNA and protein expression of TGF-β1 and CTGF of rats in NPs group were both decreased(P<0.01).Conclusions EMD-PLGA NPs could thus play an effect of inhibiting renal fibrosis and slowing the progress of chronic kidney disease more obviously than ordinary emodin.

Key words: Key words: emodin, polylactic-co-glycolic acid, nanoparticles, 5/6nephrectomy, chronic renal failure