刀豆蛋白A对小鼠肝线粒体结构和功能的影响

Effect of concanavalin A on structure and function of liver mitochondria in mice

目的研究刀豆蛋白A(Con A)致小鼠免疫性肝损伤时,肝线粒体结构和功能的改变。方法C57BL/6J小鼠随机分为正常对照组、Con A 10和20 mg·kg^-1组,分别尾静脉注射灭菌生理盐水、Con A 10和20 mg·kg^-1,给药8 h后,测定血清谷丙转氨酶(GPT)活性和肝组织病理变化。通过检测血清谷氨酸脱氢酶(GDH)活性评价线粒体膜通透性的改变,用透射电镜观察肝细胞线粒体结构,用高效液相色谱(HPLC)测定肝组织匀浆液中ATP,ADP和AMP含量,计算肝总腺苷酸库(TAN)及能荷水平(AEC),评价线粒体功能状态。结果与正常对照组比,Con A 10和20 mg·kg^-1组小鼠血清GPT和GDH活性均显著升高(P<0.05,P<0.01)。用透射电镜观察发现,肝细胞线粒体膜结构破坏,线粒体肿胀,形状高度不规则。功能学研究表明,小鼠肝组织中ATP含量分别降低了25.6%和38.3%(P<0.01),ADP含量分别降低了36.0%和47.1%(P<0.01),TAN水平分别降低了16.5%和18.9%(P<0.05),AEC分别降低了15.7%和28.1%(P<0.01)。结论Con A免疫性肝损伤与肝细胞线粒体膜通透性增加、肝细胞线粒体结构完整性破坏、生成高能磷酸化合物能力下降和肝细胞能量储备减少有关。

OBJECTIVE To study the effect of concanavalin A(Con A)-induced immunological liver injury in mice on the structure and function of liver mitochondria in mice.METHODS C57BL/6J mice were randomly divided into normal control group,Con A 10 and 20 mg·kg^-1 groups.Each group was iv injected by tail vein.The mice were sacrificed 8 h after administration.Serum gultamic pyruvic transaminase(GPT)were detected and histopathological staining was used to assess the severity of liver damage.Changes in serum glutamate dehydrogenase(GDH)activity were used to evaluate the permeability of mitochondrial membrane.Transmission electron microscopy was used to observe the mitochondrial structure of hepatocytes.The contents of adenosine triphosphate(ATP),adenosine diphosphate(ADP)and adenosine monophosphate(AMP)were determined with a high performance liquid chromatography(HPLC)method while the total adenine nucleotide(TAN)and adenylate energy charge(AEC)of the liver were calculated to evaluate the function of mitochondria.RESULTS Compared with the normal control group,the serum GPT and GDH activities of the mice in Con A groups were significantly increased.Transmission electron microscopy showed that the mitochondrial membrane structure of hepatocytes was damaged,mitochondria became swollen,and the shape was highly irregular.Functional studies showed that the ATP content in mouse liver tissues was reduced by 25.6%and 38.3%,the level of ADP by 36.0%and 47.1%,the TAN level by 16.5%and 18.9%,and that of AEC by 15.7%and 28.1%,respectively.CONCLUSION Con A-induced liver damage in mice results in increased permeability of mitochondrial membrane in hepatocytes,so that the mitochondrial structural integrity of hepatocytes is significantly disrupted,the ability to generate high-energy phosphate compounds is significantly weakened,and liver cell energy reserves are significantly reduced.These results suggest that mitochondrial damage be involved in Con A immune liver injury.