缺硒饲养ICR小鼠加快肠道病毒71型在体内的复制研究

目的观察硒蛋白对手足口病病原体肠道病毒71型（EV71）在感染动物体内复制的影响情况。方法将30只雌性ICR小鼠分为常规饲料组、缺硒饲料组和加硒饲料组，各种饲料饲养小鼠6周后，通过电感耦合等离子体质谱仪（ICP—MS）测定小鼠外周血中硒的含量以及荧光定量PCR方法测定动物体内肠道病毒EV71的载量．然后用病毒空斑实验测定病毒滴度并用酶促法来测定主要硒蛋白酶的活性。结果通过测定外周血中硒的含量发现，缺硒饲料组的ICR小鼠硒含量为0．081μg／g，显著低于常规饲料组0．135μg／g和加硒饲料组的0．128μg／g，差异有统计学意义（P〈0．01）；用荧光定量PCR方法测定EV71载量，加硒饲料组ICR小鼠体内EV71核酸扩增Ct值，明显高于缺硒饲料组（P〈0．05）；ICR小鼠体内主要硒蛋白酶（GPX1）的活力在缺硒饲料组的动物体内显著低于加硒饲料组：病毒空斑实验结果表明，缺硒饲料组的ICR小鼠体内EV71病毒复制活力显著高于其他两组。结论缺硒可能导致硒蛋白GPX1合成减少或其活力降低从而加快EV71在宿主内的复制。

Deficiency of selenium in the feeding for ICR mice accelerates enterovirus 71 replication

Objective To study the effect of deficiency of selenium in the feeding on the replication of EV71 virus in mice. Methods 30 female ICR mice were randomly divided into conventional diet group, selenium free diet group and selenium diet group, ICR mice were fed with feeding without selenium. Blood selenium was detected by ICP-MS method. EV71 loading was determined by PCR. EVT1 titer was determined by plaque assay. Selenium protease activity was dteremined by enzymatic method. Results The content of selenium in the peripheral blood test showed that selenium free diet group of ICR mice was significantly lower than the conventional diet group and selenium diet group （P〈0.01）. The result of quantitative PCR determination of EV71 load showed that selenium diet group ICR mice had a higher EV71 load than that of selenium free diet group. The selenium protease （GPX1） activity in selenium free diet group was significantly lower than that of the selenium diet group. The plaque assay result showed that selenium free diet group had a higher titer of EV71 virus than those of the other two groups. Conclusion These results suggest that selenium may be important for the synthesis of selenoproteins which can supress the replication of EV71 virus in the host.