琐琐葡萄多糖对小鼠免疫性肝损伤的保护作用及机制研究

目的观察琐琐葡萄多糖(VTP)对卡介苗(BCG)联合脂多糖(LPS)诱导小鼠免疫性肝损伤的保护作用,并探讨其作用机制。方法昆明种雄性小鼠72只,随机分为正常对照组、模型组、联苯双酯(DDB)阳性对照组以及VTP低、中、高剂量组共6组。除正常对照组外,其余各组均经尾静脉注射BCG致敏,次日起,除正常对照组和模型组给予蒸馏水外,阳性对照组灌胃给予DDB溶液200mg/kgbw,VTP低、中、高剂量组分别灌胃给予VTP溶液50、150、300mg/kgbw,连续12d。D12,除正常对照组外,其余各组均经尾静脉注射LPS,12h后采血,取肝脏、脾脏,分别测定脏器系数、生化指标、免疫指标,并观察肝脏病理组织学变化。结果VTP可显著降低免疫性肝损伤小鼠的肝脏系数和脾脏系数;并可显著升高小鼠肝组织中ALT、AST和SOD活性,降低MDA和NO含量;各组小鼠外周血中CD4+、CD8+细胞亚群比例无显著变化,但VTP可在一定程度上调节INF-γ、IL-2、IL-4和IL-10的分泌,恢复Th1/Th2细胞的平衡;病理组织学检查结果显示VTP可改善肝组织病理损伤,与生化检查结果相一致。结论VTP对小鼠免疫性肝损伤具有一定的保护作用,其作用机制可能与VTP的抗氧化功能及免疫调节功能有关。

THE PROTECTIVE EFFECTS OF POLYSACCHARIDE FROM VITIS VINIFERAL ON IMMUNOLOGICAL LIVER INJURY IN MICE AND ITS MECHANISM

Objective To study the protective effects of polysaccharide from Vitis viniferal (VTP) on Bacillus Calmette Guerin (BCG) and lipopolysaccharides (LPS) induced immunological liver injury model in mice and its mechanism. Method Seventy two healthy Kunming mice were randomly divided into six groups: control group, immunological liver injury model group, diphenyl dicarboxylate (DDB) positive control group and low, middle and high dose groups of VTP. Beside the control group, the mice in other groups were injected BCG by tail vein. Next day, the control and model group were given water, DDB positive control group with DDB (200mg/kg bw), the low, middle and high dose group of VTP with VTP 50, 150, 300 mg/kg bw respectively given i.g during 12 d. On D 12, beside the control group, all mice were injected with LPS by tail vein and were killed 12h later. Blood, serum, liver and spleen were sampled for detecting the biochemical and immunological indices, and the pathological changes of liver. Results Treatment with different doses of VTP could significantly reduce liver and spleen index, increase activities of ALT, AST, SOD and decrease contents of MDA and NO in liver tissue of mice. The ratio of CD4+ and CD8+ in plasma had no significant change, but VTP could modulate the secretion of INF-γ, IL-2, IL-4 and IL-10 in a certain extent and resume the balance of Th1 and Th2. Histopathological observations also showed that VTP could ameliorate the liver injury in different degrees and were correlated with the biochemical parameters. Conclusion Polysaccharide from Vitis viniferal has significantly protective effects against immunological liver damage induced by BCG plus LPS in mice and its mechanism might be relative to antioxidative activity and immune modulation.