ABSTRACT
Objective To investigate the effect and mechanism of necrostatin-1 (Hec-1) on the level of HMGB-1 protein in liver of rats with hemorrhagic-traumatic shock.Methods A number of 96 male SD rats were divided into sham-operated group,dimethyl sulfoxide (DMSO) group and Nec-1 group (n=32in each) by randomized number method.Rat model of hemorrhagic-traumatic shock was made by fracture of femoral bone and tibia bone and exsanguination from femoral vein until 30 mmHg and maintained at 30-40 mmHg for 90 min,then the shed blood was transfused back with Ringer's solution.The rats in shamoperated group were only under anesthesia for separating and ligating blood vessels,without exsanguination to induce hemorrhagic shock and without replenishment with blood.Rats in Nec-1 group were given 1 mg/kg Nec-1 through femoral vein 5 min before replenishment with blood and Ringer' s solution,while the rats in DMSO group were given equal volume of DMSO solution instead.Eight rats in each group were sacrificed separately at 2 h,8 h,16 h and 24 h after replenishment.The serum and liver tissues of rats in each group were collected to detect serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST),and to observe the pathological changes in liver with hematoxylin-eosin (HE) staining.The level of HMGB-1 in serum was detected by using ELISA.The cytoplasm protein and total protein expressions of HMGB-1 were assessed by using western blot analysis.Results Compared with DMSO group,levels of serum ALT at 8 h (P ＜0.05),16 h (P ＜ 0.01) and 24 h (P ＜ 0.01) in Nec-1 group were significantly lower.Level of serum AST in Nec-1 group were lower compared with DMSO group at 8 h (P ＜ 0.01),16 h (P ＜ 0.01) and 24 h (P ＜0.01).Compared with DMSO group,levels of serum HMGB-1 at 8 h (P ＜ 0.05),16 h (P ＜0.01) and 24 h (P ＜ 0.01) in Nec-1 group were significantly lower.Under light microscopy and transmission electron microscope,hepatic lobule destroyed,the blood extravasated,the immunocyte infiltrated and cellular organelle destroyed were found.Compared with DMSO group,the level of HMGB-1 protein in cytoplasm protein in Nec-1 group were significantly decreased at 8 h (P ＜ 0.01),16 h (P ＜0.01) and 24 h (P ＜0.01).The level of HMGB-1 protein in total protein in Nec-1 group were significantly decreased 8 h (P ＜ 0.05) and 24 h (P ＜ 0.05).Conclusions Nec-1 can remarkably protect the liver of rats with hemorrhagic-traumatic shock,decrease the level of HMGB-1,and protect the hepatocyte effectively.
ABSTRACT
Objective To investigate the effects of necrostatin-1 (Nec-1) on the liver of rats with trauma induced hemorrhagic shock.Methods 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 and 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,while the rats in model 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-oα (TNF-α) and interleukin-1β (IL-1β) in the liver were detcrmined 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.Results Compared with 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 ± 47.11; 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-1β 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-1β 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-1β 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].Conclusion 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.
ABSTRACT
Objective Traumatic hemorrhagic shock ( THS) is frequently complicated by liver injury , and IL-1βis one of the important inflammatory factors involved in this process .We ob-served changes of liver injury-related indexes in the rat model of THS and investigated the effects of AS-1, the mimic of the TIR/BB loop of Myd88, an important molecule of the IL-1βsignal pathway, on liver injury triggered by ischemia/reperfusion following THS and resuscita-tion ( THSR) in rats. Methods Thirty-two healthy male SD rats were randomly divided into groups A (THSR), B ( THSR+AS-1), C (THSR+dissolution medium), and D (control).For those of the first three groups , fracture was induced in the left tibia , the mean arterial pressure reduced to 30 mmHg by bloodletting from the femoral artery and maintained at 30-40 mmHg for an hour , and then the rats resuscitated by infusion of blood and Ringer′s solution in proportion at a uniform speed in 30 min.Before resuscitation, the rats in group B were treated with AS-1 (160 mg/kg), group C with dissolution medium, and group D left untreated .At 3 hours after resuscitation in groups A , B and C, and at 3 hours after 2.5h-our in-tubation in group D , we detected the activity of ALT , the levels of AST , IL-1βand TNF-α, and the activity of MPO in the left liver , and observed pathological changes in the liver by light microscopy . Results Compared with group D, groups A, B and C showed ev-ident liver injury and significant increases in the activity of ALT (87.55 ±6.8 vs 206.13 ±23.67, 110.45 ±18.20 and 210.73 ± 28.43), AST (327.03 ±36.23 vs 621.00 ±40.61, 409.13 ±63.53 and 600.25 ±44.05), the levels of IL-1β(327.03 ±36.23 vs 621.00 ±40.61, 409.13 ±63.53 and 600.25 ±44.05) and TNF-α(93.51 ±9.86 vs 214.13 ±21.24, 145.25 ±12.42 and 206.50 ± 36.97), and the activity of MPO (0.90 ±0.21 vs 1.72 ±0.12, 1.20 ±0.11 and 1.67 ±0.14) (all P0.05).Conclusion TIR/BB-loop mimetic AS-1 can attenuate ischemia/reperfusion-induced liver injury after THSR in rats by decrea -sing the levels of IL1-βand TNF-αin the serum.