TGF-beta1 immunohistochemistry and promoter methylation in chronic renal failure rats treated with Uremic Clearance Granules.

The aim of the study was the explain the mechanism related to therapeutic effects of Uremic Clearance Granules (Niaoduqing Keli in Chinese) on adenine-induced Chronic Renal Failure in rats. Thirty 8-week-old male Wistar rats were selected and randomly divided in to 3 groups: Normal Control Group (NCG)consisted of 10 rats, Chronic Renal Failure Pathological Control Group (PCG) 10 rats, and Uremic Clearance Granules Treatment Group (UCG) 10 rats. Each rat in PCG and UCG was fed with adenine-enriched diets, containing 10 g adenine per kg food for 6 weeks. After fed with adenine, each rat in UCG was administered orally with 2 ml solution of Uremic Clearance Granules for 6 weeks. The concentration of Uremic Clearance Granules solution was 0.42 g/ml which was 10 times of human. On days 42 and 84, the serum levels of creatinine, Blood Urea Nitrogen and homocysteine were determined. The methylation of TGFbeta1 promoter was tested by methylation-specific PCR. TGF-beta1 mRNA and protein expression in rat renal cortex were analyzed by real-time RT-PCR and Immunohistochemistry. (1) Experimented on model of Chronic Renal Failure in rats, the preparation was proved to be able to reduce serum creatinine, Blood Urea Nitrogen, and homocysteine (p<0.05), improve renal function. (2) The expression of TGF-beta1 in mRNA and protein level were down-regulated. (3) TGF-beta1 promoter was demethylated at some loci in PCG, and was recovered in UCG. After treatment with Uremic Clearance Granules, the Chronic Renal Failure Wistar rat's kidney function was recovered. The recovery may be result of the remethylation of TGF-beta1 promoter and then lead to TGF-beta1 be transcripted and translated normally. The experimental study explain the molecular mechanism by which Uremic Clearance Granules treat Chronic Renal Failure.