Protective effect of necrostatin-1 on the liver of rats with trauma induced hemorrhagic shock

Abstract

To investigate the effects of necrostatin-1( Nec-1) on the liver of rats with trauma induced hemorrhagic shock. Trauma induced hemorrhagic shock model was produced by adopting the left femur, tibia fracture and soft tissue injury, bleeding and reperfusion in male Sprague-Dawley (SD) rats. A total of 22 rats were divided into model group and Nec-1 group with 11 rats in each group by randomized digital number method and the 72-hour mortality was observed. In addition, 72 rats were randomly divided into sham group, model group, Nec-1 group with 24 rats in each group. Rats in sham group were only received anesthesia, separating a nd ligating blood vessels, without trauma induced hemorrhagic and reperfusion, and the rats in Nec-1 group were received 1 mg/kg Nec-1 through femoral vein 5 minutes before reperfusion, and the rats in Nec-1 group were received the same amount of solvent. The serum and liver tissues of each group were collected at 2, 4, 8 hours after reperfusion. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were detected by automatic biochemistry analyzer. The pathology changes in liver were observed by hematoxylin-eosin (HE) staining. The mRNA expressions of tumor necrosis factor-α (TNF-α) and interleukin -1β (IL-1β) in the liver were determined by reverse transcription-polymerase chain reaction (RT-PCR). The protein expressions of receptor interaction of protease 1/3( RIP1/RIP3) were also assessed by Western blot analysis. Compared to the model group, Nec-1 significantly reduced the 72 hour mortality [18.18% (2/11) vs. 63.64% (7/11), P = 0.040]. Two hours after trauma induced hemorrhagic shock and reperfusion, the expressions of ALT and AST in model group were significantly increased compared with those in sham group. [ ALT (U/L): 110.21 ± 22.32 vs. 80.98 ± 19.94, AST (U/L): 364.29 ± 64.83 vs. 279.76 ± 70.64, both P<0.05], and reached the peak at 8 hours [ALT (U/L): 387.41± 47.11 vs. 82.76 ±22.44, AST ( U/L): 973.35 ±77.51 vs.261.49 ± 52.03, both P <0.01]. Levels of serum ALT and AST in NEc-1 group were significantly decreased compared with model group [ALT (U/L) 4 hours: 144.64 ± 33.79 vs. 213.96 ± 36.21, 8 hours: 159.48 ± 43.57 vs. 387.41>11; AST (U/L): 4 hours: 398.78 ± 59.48 vs. 630.61 ± 59.93, 8 hours: 427.38 ± 80.75 vs. 973.35 ± 77.51, all P < 0.01] Under light microscopy, it was noted that the hepatic sinus expansion, liver cells degeneration, necrosis, as well as infiltration of abundant inflammatory cells were observed. But the pathology changes in hepatic tissues were significantly mitigated in Nec-1 group. Along with the time extension, the mRNA expressions of TNF-α and IL-β and the protein expressions of RIP1 and RIP3 were markedly up-regulated. Compared with model group, difference in the mRNA expressions of TNF-α and IL-β in hepatic tissues in Nec-1 group were statistically significant, and the most obvious difference was at 8 hours [TNF-α mRNA: 1.457 ± 0.081 vs. 2.317 ± 0.062, IL-β mRNA: 0.690 ± 0.087 vs. 1.812 ± 0.112, both P<0.01]. But there was no statistically significant difference in RIP1 and RIP3 between Nec-1 group and model group [RIP1 protein 8 hours: 0.561 ± 0.033 vs. 0.587 ± 0.036, RIP3 protein 8 hours: 0.976 ± 0.040 vs. 1.044 ± 0.115, both P > 0.05]. Nec-1 may be remarkable protect effect on the liver of rats with trauma induced hemorrhage shock and reperfusion, and the intrinsic mechanisms need further investigation.