Protective effects of a c-jun N-terminal kinase inhibitor, SP600125, against D-galactosamine/lipopolysaccharide induced acute liver failure in mice / 中华传染病杂志

ABSTRACT

Objective To investigate the protective effect of c-jun N-terminal kinase (JNK)inhibitor SP600125 against acute liver failure in mice.Methods Fifty-five male C57/BL6 mice were divided into control group (n =30) and SP600125 group (n =25).The animals were given an intraperitoneal injection of D-galactosamine (D-GalN,400 mg/kg body weight)/lipopolysaccharide (LPS,30 μg/kg body weight).The control group and SP600125 group were given 10％ dimethyl sulfoxide (15 mL/kg body weight) or SP600125 (75 mg/kg body weight) subcutaneously 12 h and 1 h before D-GalN/LPS administration,respectively.D GalN/LPS induced mouse JNK activation was detected by immunohistochemistry for phospho JNK (p-JNK).D-GalN/LPS induced mouse liver cell apoptosis was detected by immunohistochemistry for Caspase-3 and TdT-mediated-dUTP nick endlabeling (TUNEL).Serum alanine transaminase (ALT) level was tested to assess liver injury.Survival rate of mice within 24 h after D-GalN/LPS administration was observed.The comparison between groups was done by t test and survival rate was analyzed by Kaplan-Meier method.Results JNK activity in liver tissues,as indicated by observation of p-JNK positive cells by immunohistochemistry,was diminished 4 h after D-GalN/LPS administration in SP600125 group.Reduced Caspase-3 activity was observed 6 h after D-GalN/LPS administration in SP600125 group (as indicated in immunohistochemistry by Caspase-3 positive cells).Mice in SP600125 group showed significantly lower TUNEL-positive cell count than control group (43.0±24.5 vs 194.7±73.8; t=9.743,P=0.000).Serum ALT level 6 h after D-GalN/LPS administration was (24.0±54.7) U/L in SP600125 group,which was significantly lower than that in control group [(1234.4±478.4) U/L; t=4.734,P=0.0015].SP600125 also significantly improved the survival rate within 24 h after D-GalN/LPS administration (4/5 vs 1/10； x2=5.225,P=0.0223).Conclusions JNK inhibitor SP600125 exerts protective effects against D-GalN/LPS induced acute liver failure in mice by suppressing JNK activation and hepatocyte apoptosis.