Protective effect of salvianic acid A on hepatic ischemia reperfusion injury in rats

Objective To study the protective effect of salvianic acid A on hepatic ischemia reperfusion (I/R) injury in rats. Methods Sixty SD rats were randomly divided into 3 groups (20 rats in each group): sham operation (Sham) group, I/R group, Salvianic acid A preconditioning (Sal+ I/R) group. The portal vein, hepatic artery and bile duct of the middle lobe and left lobe of the liver were dissected, and clipped by the small blood vessel clamp to make the left and middle lobe ischemia. The blood flow was restored after 1 h, and the model of I/R was constructed. In the sham operation (Sham) group, dissection was done at the same step without blocking blood flow. In Sal+ I/R group, Salvianic acid A (40 mg/kg) was injected through the tail vein 60 min before ischemia. After reperfusion for 6 h, 10 rats were randomly selected from each group. Blood samples were collected through the inferior vena cava and liver tissue samples were taken. After reperfusion for 12 h, the remaining rats were treated by the same method. The activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in serum were determined. The levels of glutathione peroxidase (GPX) and superoxide dismutase (SOD) were measured in liver tissues. The pathological changes of liver tissue were observed by hematoxylin and eosin (HE) staining and light microscopy. Results The levels of ALT, AST, IL-6 and TNF-α in the Sal+ I/R group [6 h: (350.47±69.65), (500.25±76.12) U/L, (165.32±23.46), (65.31±9.52) ng/L; 12 h: (250.47±36.78), (355.25±59.12) U/L, (130.65±34.31), (103.38±18.46) ng/L were lower than those in the group I/R [6 h: (550.34±82.31), (702.28±106.48) U/L, (300.13±49.28), (95.55±29.21) ng/L; 12 h: (490.34±89.68), (550.28±64.23) U/L, (260.00±60.08), (180.32±38.12) ng/L, P=0.019]; The levels of GPX and SOD in the Sal+ I/R group [6 h: (52.34±11.59), (63.00±19.23) pg/ml; 12 h: (68.32±21.45), (81.00±17.65) pg/ml] were higher than those in the group I/R [6 h: (30.12±5.12), (43.00±7.45) pg/ml; 12 h: (39.58±3.16), (54.00±8.46) pg/ml, P=0.029], the injury of the liver tissue in the Sal+ I/R group was lighter than that in the group I/R under light microscope. Conclusion Salvianic acid A could lower the levels of IL-6 and TNF-α in serum after the I/R injury in rats, raise the levels of GPX and SOD in liver tissue and reduce the degree of liver damage after I/R. Key words: Salvianic acid A; Liver ischemia reperfusion injury; Reactive oxygen species