黄蜂毒素1对内毒素／脂多糖所致小鼠急性肝损伤的影响

Effect of mastoparan-1 on lipopolysaccharide-induced acute hepatic injury in mice

目的了解黄蜂毒素1（MP-1）对LPS所致小鼠急性肝损伤的影响，探讨其作用机制。方法将104只BALB／c小鼠按随机数字表法分为健康对照组（8只，不作任何处理）、LPS组（48只，尾静脉注射LPS5mg／kg）和MP-1组（48只，尾静脉注射LPS5mg／kg和MP-13mg／kg）。后2组小鼠于注射后2、6、12、24、48、72h处死，每组每时相点8只，采集血和肝组织标本。动态比浊法鲎试验检测2组小鼠各时相点血浆LPS水平，酶联免疫吸附测定法检测血浆TNF-α和IL-6水平，全自动生化分析仪检测血清丙氨酸转氨酶（ALT）和天冬氨酸转氨酶（AST）水平，实时荧光定量RT-PCR检测肝组织Toll样受体4（TLR4）、TNF-α和IL-6mRNA表达，观察注射药物后各时相点肝组织病理变化。另取健康对照组小鼠相同样本进行以上检测。结果与健康对照组比较，LPS组小鼠血浆LPS和TNF-α水平在注射药物后2h迅速升高，各为（18320．50±2782．50）EU／mL和（988±130）ng／L，此后逐渐下降，72h降至（1．80±0．80）EU／mL和（150±44）ng／L，接近健康对照组水平；IL-6、ALT和AST逐渐升高，12h达峰值，随后下降，72h接近健康对照组水平；LPS组小鼠肝组织TLR4、TNF-α和IL-6mRNA表达也在注射后明显增强，12～48h时肝组织炎性反应性病理改变最为显著。与LPS组比较，MP-1组小鼠LPS、细胞因子和转氨酶水平在注射后不同程度地降低（P〈0．05或P〈0．01），肝组织相关基因表达受到抑制（P〈0．05或P〈0．01），病理改变较轻。结论MP-1可能通过中和LPS，减少其诱导的炎性介质合成与释放，进而减轻小鼠肝组织的损伤。

Objective To observe the effect of mastoparan-1 （MP-1） on lipopolysaccharide （LPS）-induced acute hepatic injury in mice and probe into its possible mechanism. Methods One hun-dred and four BALB/c mice were randomly divided into healthy control group（ n = 8, without treatment, HC） , LPS group （n =48, with injection of LPS 5 mg/kg via tail vein） , and MP-1 group （n =48, with injection of LPS 5 mg/kg and MP-1 3 mg/kg via tail vein）. Mice in LPS group and MP-1 group were sacri- ficed at 2^nd, 6^th, 12^th, 24^th, 48^th and 72^nd post injection hour （PIH）, 8 mice at each time point in each group. Blood samples were collected for determination of plasma levels of LPS by kinetic turbidimetric limu- lus test, TNF-α and IL-6 by ELISA, serum levels of ALT and AST by automatic biochemistry analyzer respectively. Hepatic tissue samples were collected for determination of TLR4, TNF-α and IL-6 mRNA by real-time fluorescent quantitation reverse transcription polymerase chain reaction, along with the observation of pathological changes in hepatic tissue at each time point. Above-mentioned examinations were also performed in HC group. Results Compared with those of HC group, plasma levels of LPS and TNF-α in LPS group significantly increased at 2^nd PIH（ 18 320.50± 2782.50 EU/mL and 988±130 ng/L, respectively） , then decreased gradually to 1.80±0.80 EU/mL and 150±44 ng/L at 72^nd PIH, which was close to those of HC group. The values of IL-6, ALT and AST peaked at 12^th PIH, which declined to the levels close to those of HC group at 72^nd PIH. Meanwhile, the expressions of TLR4, TNF-α and IL-6 mRNA in liver were remark- ably up-regulated after injection, and the pathological changes in hepatic tissue pronounced significantly at 12A^nd , 24^th and 48^th PIH. Compared with those of LPS group, the levels of LPS, cytokines, ALT and AST decreased in MP-1 group in different degrees after injection （ P 〈 0.05 or P 〈 0.01 ） , genes expression（ P 〈 0.05 or P 〈0. 01 ） and pathological changes was respectively suppressed and alleviated in hepatic tissue. Conclusions MP-1 can alleviate LPS-indueed acute hepatic injury in mice, which may be associated with its neutralization of LPS and attenuation of synthesis and release of inflammatory mediators.