Protective Effect Of Mild Hypothermia On The D-GalN/LPS Induced Acute Liver Failure In Rats

Objective：Explore the protective effect of mild hypothermia on the D-GalN/LPS-inducedacute liver failure in rats, study the effect of mild hypothermia on acute liver failurerats’ serum ALT, AST, TNF-alpha, IL-10, as well as Hepatic cytochrome c/caspase3protein’expression.Method：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 normal saline.mildhypothermia group immediately began mild hypothermia treatment after injection ofD-GalN/LPS. Each groups were taken specimens at4h,8h and12h after ALFinduction.2、Referance to Kim’s method,we sprayed alcohol and haired mild hypothermiagroup’s rat body to ensure the rat rectal temperature to fall to the predeterminedtemperature (32to35℃) within the specified time (15-20min).Rectal temperaturewas detected every15min during the first1hour,then it was changed to every30minutes.The important thing was that the rectal temperature must be maintained tothe range between32°C to35℃until the end of the experiment.3、Each group was detected serum ALT and AST concentration, observed liverpathological changes by HE staining, evaluated serum TNF-α and IL-10concentration by ELISA assay,and determined the protein expression levels of livercytoplasm cytochrome C and caspase3by Western blot assay.Result:1、Levels of serum ALT, AST in mild hypothermia group were significantly lowerthan model group at the same time point in8h and12h(ALT8h P=0.049，12hP=0.039；AST8h P=0.014，12h P=0.024), and had no significant differences compared with the model group at4h(ALT P=0.43，AST P=0.19).2、 we could find pathomorphology normal of the control group liver tissue ateach time point by HE staining, model group and mild hypothermia group rat livertissue pathological changes were more and more serious with the time going by.After implementing mild hypothcrimia, the liver had no obvious improvement at thetime of4h and8h. But hypothermia group liver cell necrosis and inflammatory cellinfiltration range decreased than model group at12h, and it residual more liver cells.3、The blood serum TNF-α of mild hypothcrimia group was obvious lower thanthe model group’s at the time of4h (P=0.021), But at the time of8h and12h the mildhypothcrimia group and model group had no significant difference(8h P=0.209；12hP=0.093). The level of IL-10in serum no significant differences between relativelytime points of mild hypothermia group compared with the model group(4h P=0.545，8h P=0.389；12h P=0.169).4、Expression of Cyt C protein down-regulate in hypothermia group hepaticcells compared with the model group at8h(P=0.001),but expression of Cyt C proteinhad no significant difference compared with the model group at4h and12h(4hP=0.829，12h P=0.061).5、The expression of activatory cleaved-caspase3protein of liver in mildhypothcrimia was significantly less than the model group at the time of8h(P=0.016),but at the time of4h and12h the difference of them had no statistical significance(4hP=0.790，12h P=0.619).Conclusion:The study found that level of serum ALT, AST, TNF-α in acute liver failure ratswere decreased and improved pathological changes in via hypothermia treated. wefound that liver cell mitochondrial were less release cytochrome C and less cleavagecaspase3intracellular. Also we found that level of serum IL-10had no significantdifferences after acute liver failure rats via hypothermia treatment.This study showsthat mild hypothermia play a protective role on liver cells of acute liver failure.