Effect Of Mild Hypothermia On High Mobility Group Box1Protein In Rats With Actue Liver Failure

Objective:To investigate the liver tissue and blood of HMGB1variation in rats with acuteliver failure and the effect of mild hypothermia on high mobility group box1proteinin rats with actue liver failure.Methods:1.72SD rats were randomly divided into control group (n=24), model group (n=24) and mild hypothermia group (n=24). D-GalN (400mg/kg) and LPS (100μg/kg)were uesd to manufacture of acute liver failure model by intraperitoneal injection.Model group and mild hypothermia group were all given D-GalN/LPS byintraperitoneal injection,simultaneously,control group was given the same amount ofsaline.2.Mild hypothermia group immediately began mild hypothermia treatment afterinjection of D-GalN/LPS.Referance to Kim’s method,we sprayed alcohol and hairedmild hypothermia group’s rat body to ensure the rat rectal temperature to fall to thepredetermined temperature (32to35℃) within the specified time (15-20min). Inorder to ensure the stability of the rectal temperature in rats,the rectal temperature wasdetected once every15min during the first1hour and if the temperature fluctuationsis not changed,then it was tested once every30minutes.3.Each groups were taken specimens at4h,8h and12h after ALF induction.Eachgroup was detected serum ALT and AST concentration, observed liver pathologicalchanges by HE staining, evaluated serum HMGB1concentration by ELISA assay,anddetermined the level of HMGB1mRNA by RT-PCR and the protein expression levelof liver tissue HMGB1by immunohistochemistry..Results:1.The liver tissue pathological results of model group were that they were moresevere with time.In12h time point,the hepatic lobule normal structure disappeared with confluent necrosis more than2/3of the entire slice area,a large number of celldebris and only a small amount of normal liver cells remained,eosinophilic changesignificantly increased, a large number of inflammatory cells soak Run, sinusoidalcongestion and bleeding obvious, and serum ALT, AST levels increased withtime,these pathological changes were consistent with acute liver failure pathologicalchanges and the acute liver failure model was successed.2.The serum HMGB1concentrations of control group were lower at all timepoints,and the serum HMGB1concentrations of the model group and the mildhypothermia group increased with time. Serum HMGB1concentration of mildhypothermia group were lower than the model group at each time point, but only at8h,12h time point difference was statistically significant (8h P <0.001,12h, P=0.006).3. The liver tissue of HMGB1mRNA expression of control group were lower atall time points,while the liver tissue HMGB1mRNA expression of model group andmild hypothermia group were increased gradually over time. Compared with modelgroup,mild hypothermia group liver tissue HMGB1mRNA expression were morelower at all time points, and8h,12h time point difference was statistically significant,P values were respectively0.016,0.006.4. Liver nuclei and cytoplasm of the control group only saw a small amount ofHMGB1protein expression in liver tissue,the model group and mild hypothermiagroup HMGB1protein expression increased with time, the degree of staining anddyeing range of mild hypothermia group and model group at4h,8h point was nosignificant difference and in the12h time point, degree of staining mild hypothermiagroup was consistent with the model group,but dyeing range was less than the modelgroup.5.The liver pathological changes of mild hypothermia group at4h,8h point wereno significant difference compared with the model group. The hepatocellular necrosisrange of mild hypothermia group at the12h time point was more smaller,had slightlyless cellular debris and more normal liver cells remained than the model group.Conclusion：1. The way to induced acute liver failure model by intraperitoneal injection of D-GalN (400mg/kg)+LPS (100μg/kg) was successed.2. The blood and liver tissue HMGB1levels of rats with acute liver failureincreased with time,there was a positive correlation between them and the degree ofliver damage.3. Mild hypothermia could reduce the serum HMGB1level,inhibit liver tissue torelease HMGB1and mitigate the liver tissue damage,protect the liver of ALF.