Experimental study of the effects of simvastatin on peritoneal fibrosis relating to peritoneal dialysis

【Objective】To investigate the effects of simvastatin on peritoneal form and function and the expression of transforming growth factor-β1 (TGF-β1) in rat model of peritoneal dialysis and its potential mechanism of prevention peritoneal fibrosis.【Methods】Rat model of peritoneal fibrosis was induced by high glucose dialysate (4.25%, Baxter) and lipopoly saccharide (LPS). The rats were randomly divided into three groups: Control group, model group, and sim-vastatin treating group. 20 mg/kg/d of simvastatin was given orally to rats by gastric gavage in the morning once a day. Thirty days later all rats were sacrificed. The peritoneal membrane function was investigated by peritoneal transport test; The abdominal membrane was stained with Masson method. The peritoneal collagen thickness was measured. TGF-β1 mRNA expression was examined with real time polymerase chain reaction(RT-PCR). TGF-β1 in dialysate was detected by ELISA method. 【Results】 Masson stain showed that the peritoneum thickness was significantly increased in the model group than in other groups (P 0.05), and collagen deposition was evident in the thickened submesothelial compact zone. The ultrafiltration volume was lower in model group than in other groups (P 0.05). With the treatment of simvastatin, pathological changes were significantly lessened. The ultrafiltration volume was increased in simvastatin treating group than in model group (P 0.05). The expression of TGF-β1 mRNA in peritoneum was significantly increased in the rats model (P 0.05), but the levels in the simvastatin treated group were lower than those of the untreated group (P 0.05), and the concentration of TGF-β1 also decreased obviously in simvastatin treating group (P 0.05). 【Conclusion】 simvastatin could decrease the expression of TGF-β1 in peritoneum and delay the progression of peritoneal fibrosis.