Experimental Study On The Protective Effect Of Ligustrazine On The Transporting Function Of Hepatocellular Mitochondria Membrane In Rats With Acute Liver Injury Induced By Sepsis

Objective Mitochondrial damage is one of the main mechanisms of sepsis-induced acute liver injury.The function of mitochondrial membrane transport is the basic condition for maintaining mitochondrial function.Mitochondrial membrane regulate the transport of ions,water and fatty acids to maintain the stability of the mitochondria and regulate the synthesis and metabolism of cells.This study is to investigate the protective effect of ligustrazine on the transporting function of hepatocellular mitochondria membrane in the rats with sepsis-induced acute liver injury(SALI).Methods The Sprague-Dawley(SD)rats were randomly divided into sham operation group,SALI group[established by cecal ligationand puncture(CLP)],ligustrazine treatment group(injection of ligustrazine 60 mg/kg through tail vein after CLP)and ligustrazine preventive group(7 days before CLP,ligustrazine was injected daily through tail vein for 60 mg/kg),and there were 12 rats in each group.Abdominal aorta blood and liver were harvested at 10 hours after operation.The content of serum alanine aminotransferase(ALT),aspartate aminotransferase(AST)and mitochondrial aspartate aminotransferase(m-AST)were determined by enzyme coupling rate method.The content of ATP was detected by colorimetric and chemical fluorescein method.The activity of mitochondrial ATPase was detected by phosphorus quantification.The expressions of mitochondrial membrane aquaporin 8(AQP8)and carnitine palmitoyl transferase(CPT)were detected by Western Blot.Results1.Compared with sham operation group,the levels of serum ALT,AST and m-AST were significantly increased in SALI group,ligustrazine treatment group and ligustrazine preventive group.The levels of serum AST and m-AST in the ligustrazine preventive group were significant lower than those in the ligustrazine treatment group[AST(U/L):303.9±110.3 vs.427.0±117.9;m-AST(U/L):168.2±60.0 vs.239.6±64.9,both P<0.05].Meanwhile,the content of ATP was reduced,the activity of mitochondrial membrane ATPase,the expressions of AQP8 and CPT-1A were significantly decreased in SALI group,ligustrazine treatment group and ligustrazine preventive group2.Compared with the SALI group,the levels of serum ALT,AST and m-AST were significantly decreased in the ligustrazine treatment and ligustrazine preventive groups[ALT(U/L):123.8±32.8,105.0±44.5 vs.233.0±110.1;AST(U/L):427.0±117.9,303.9±110.3 vs.742.6±441.4;m-AST(U/L):239.6±64.9,168.2±60.0 vs.412.8±252.6;all P<0.01],the content of ATP were significantly increased(nmol/mg:29.5±10.3,34.6±11.2 vs.19.3±8.8,both P<0.01)3.The activity of ATPase in hepatocellular mitochondrial membrane were significantly increased[percentage increase from SALI group(100%),Na+-K+-ATPase(U/mg):3.91±0.30,3.97±0.35 vs.2.87±0.82;Mg 2+-ATPase(U/mg):3.75±0.38,3.88±0.35 vs.2.64±1.06;Ca 2+-ATPase(U/mg):3.15±0.58,2.98±0.31 vs.1.75±1.25;Ca2+-Mg2+-ATPase(U/mg):3.82±0.31,3.91±0.42 vs.2.57±1.01,all P<0.01]4.The expressions of AQP8 and CPT-1A were significantly increased[percentage increase from SALI group(100%),AQP8/COX-IV:(79.12±7.79)%,(88.40±9.22)%vs(62.08±11.91)%;CPT-1A/COX-IV:(87.92±10.06)%,(84.91±17.48)%vs.(72.11±7.82)%,all P<0.01].There was no significant difference in the expression of CPT-2 in mitochondrial membrane between the four groupsConclusion1.The sepsis model can be established by cecal ligation and puncture(CLP)in SD rats and lead to acute liver injury,which resulted in elevated levels of ALT,AST,and m-AST.2.When sepsis-induced acute liver injury occurs,the activities of Na +-K ?-ATPase,Mg2+-ATPase,Ca2+-ATPase and Ca2-Mgr+-ATPase in mitochondrial membrane,the expression of AQP-8,CPT-1A protein and the content of mitochondrial ATP decrease.3.The possible mechanisms of protective effects of ligustrazine on liver function and hepatocyte mitochondria in septic rats may include:(1)Ligustrazine can protect the function of mitochondria by stabilizing mitochondrial membrane Na+-K+-ATPase,Ca2+-Mg2+-ATPase,Mg2+-ATPase and Ca2+-ATPase activities,to improve the mitochondrial membrane ion transporting effect.(2)Ligustrazine can reduce the damage of sepsis-induced acute liver injury by up-regulating the expression of AQP 8 protein and maintaining the mitochondrial membrane water homeostasis.(3)CPT-1A may be the main target of SALI.Ligustrazine can protect hepatocyte mitochondria by restoring the expression of CPT-1A,promoting fatty acids into mitochondria and protecting lipid metabolism.