Effect And Mechanism Of NAC On Renal Fibrosis In Rats With Cardiorenal Syndrome

Objective:To investigate the effect and mechanisms of NAC on oxidative stress induced renal fibrosis in patients with cardiorenal syndrome.Methods:1. experimental group and model making: SD rats were randomly divided into sham group, operation group, sham+NAC group and operation +NAC group. The model of heart failure was established by abdominal aortic banding, then blood and kidney samples of rats were collected at four weeks after operation;2.Serum creatinine(Scr) and urea nitrogen(BUN) levels were detected by ELISA method;3.Masson staining was used to observe the renal fibrosis, and semi-quantitative analysis of the degree of renal fibrosis in each group;4.m RNA expression of TGF- beta 1, Smad3 and Smad7 in the kidney tissue of the rats were detected by RT-PCR;5.Western Blot method was used to detect the protein contentof 4-HNE, TGF- beta 1, Smad3 and Smad7 in renal tissues of rats in each group,Results:1. By detecting the cardiac hemodynamics in rats, compared to sham operation group,rats in operation group, the differences between the two groups was statistically significant(P < 0.05), according to the hemodynamic changes, the model of heart failure is successful.(these datas are from the cardiovascular hospital).2.Compare to sham group, the serum level of Scr and BUN in operation group were increased significantly(P < 0.05);Then in operation+NAC group,The level of SCR has a trend to downward when compared to operation group, but the BUN level was significantly decreased(P < 0.05).3.The Masson staining of renal suggest that compared with sham group, the level of renal fibrosis in the operation group was significantly increased, while the renal fibrosis level in operation +NAC group was significantly decreased(P<0.05) when compared with operation group.4.Compared the sham group with operation group,the m RNA expression of TGF beta 1 and Smad3 were significantly increased, the protein content of 4-HNE, TGF beta 1, and Smad3 were also significantly increased; Compared to operation group, the m RNA expression of TGF beta 1, Smad3 and the protein content of 4-HNE, TGF beta 1 and Smad3 were significantly decreased in operarion+NAC group. The m RNA expression and protein content of Smad7 didn’t see the different significantly between each groups(P>0.05).5.There was no significant difference between the sham+NAC group and the sham operation group(P>0.05).Conclusion:NAC can reduce the level of renal fibrosis which induced by oxidative stress in cardiorenal syndrome, and its mechanism may be related to reducing the expression of 4-HNE, TGF- beta 1 and Smad3.