CAJ | 학술논문

目的：探讨脂多糖预处理时糖原合成酶激酶3（glycogen synthase kinase-3, GSK-3）功能活性的变化及其对肝组织糖原代谢的影响和机制。方法雄性SD大鼠随机分为正常对照、脂多糖预处理和GSK-3抑制剂氯化锂预处理组，分别进行相应处理后再接受大剂量脂多糖（10 mg/kg）攻击以建立脂多糖诱导的急性肝损伤模型；采用PAS染色法观察肝组织糖原聚集，用试剂盒法定量检测肝组织糖原含量，以Western Blot法半定量分析GSK-3的蛋白表达和抑制性磷酸化水平，采用考马斯亮兰比色法测定肝组织钙依赖蛋白酶的活性。结果尽管大剂量脂多糖攻击后各组动物肝组织糖原含量组间比较均无显著差异（P>0.05），但均较攻击前有显著降低（P<0.05），且脂多糖和氯化锂预处理均可导致肝组织糖原含量增加（P<0.05）；尽管诱导脂多糖预处理并未改变GSK-3的蛋白表达水平（P>0.05），但导致GSK-3β抑制性磷酸化（P<0.05）和GSK-3α不完全裂解；大剂量脂多糖攻击后肝组织钙依赖蛋白酶活性较前显著升高（P<0.05），但组间比较无显著差异（P>0.05）。结论脂多糖预处理导致GSK-3β抑制性磷酸化和GSK-3α不完全裂解，促进肝组织糖原合成和聚集，但不影响钙依赖蛋白酶活性，有利于增加肝组织糖原储备并可能在遭受大剂量脂多糖攻击时提供能量需求。
목적：탐토지다당예처리시당원합성매격매3（glycogen synthase kinase-3, GSK-3）공능활성적변화급기대간조직당원대사적영향화궤제。방법웅성SD대서수궤분위정상대조、지다당예처리화GSK-3억제제록화리예처리조，분별진행상응처리후재접수대제량지다당（10 mg/kg）공격이건립지다당유도적급성간손상모형；채용PAS염색법관찰간조직당원취집，용시제합법정량검측간조직당원함량，이Western Blot법반정량분석GSK-3적단백표체화억제성린산화수평，채용고마사량란비색법측정간조직개의뢰단백매적활성。결과진관대제량지다당공격후각조동물간조직당원함량조간비교균무현저차이（P>0.05），단균교공격전유현저강저（P<0.05），차지다당화록화리예처리균가도치간조직당원함량증가（P<0.05）；진관유도지다당예처리병미개변GSK-3적단백표체수평（P>0.05），단도치GSK-3β억제성린산화（P<0.05）화GSK-3α불완전렬해；대제량지다당공격후간조직개의뢰단백매활성교전현저승고（P<0.05），단조간비교무현저차이（P>0.05）。결론지다당예처리도치GSK-3β억제성린산화화GSK-3α불완전렬해，촉진간조직당원합성화취집，단불영향개의뢰단백매활성，유리우증가간조직당원저비병가능재조수대제량지다당공격시제공능량수구。
Objective To investigate the changes in the functional activity of glycogen synthase kinase-3 (GSK-3) in the hepatic tissue after endotoxin (lipopolysaccharide, LPS) tolerance and explore the effects of LPS-induced GSK-3 inhibition on glycogen metabolism in the liver. Methods Male SD rats were randomly divided into normal control, endotoxin pretreatment and GSK-3 inhibitor (lithium chloride) groups with corresponding pretreatments prior to a large dose of LPS challenge (10 mg/kg) to induce liver injury. Glycogen deposition and content in the hepatic tissue was detected using periodic acid-Schiff (PAS) staining and a glycogen quantification kit, respectively. Western blotting was performed for semi-quantitative analysis of protein level and inhibitory phosphorylation of GSK-3, and a Coomassie brilliant blue G-250-based colorimetric assay was used to detect calpain activity in the liver. Results Glycogen content in the liver decreased significantly after LPS challenge in all the 3 groups (P<0.05) but showed no significant difference among the groups (P>0.05). Both LPS and lithium chloride pretreatments caused a significant increase of liver glycogen content (P<0.05). LPS pretreatment induced inhibitory phosphorylation of GSK-3β (P<0.05) and partial cleavage of GSK-3α but did not affect the expression of GSK-3 protein (P>0.05). Large-dose LPS challenge significantly increased the activity of calpain in the liver tissue (P<0.05) to a comparable level in the 3 groups (P>0.05). Conclusion Endotoxin pretreatment induces inhibitory phosphorylation of GSK-3β and partial cleavage of GSK-3α and promotes the deposition of liver glycogen but does not affect the activity of calpain, which may contribute to an increased glycogen reserve for energy supply in the event of large-dose LPS challenge.