硒对高碘仔鼠脑MBP基因表达的影响

目的研究高碘摄入对仔鼠脑髓鞘碱性蛋白(MBP)mRNA的影响及硒干预的作用。方法将Balbc小鼠按体重随机分为3组:正常对照组、高碘组(3mgL)以及高碘+Se组(碘3mgL+硒0.5mgL),分别喂饲高碘水或高碘+硒水以及正常鼠饲料。各组亲代鼠饲养4个月后雌雄按2∶1交配,取14天仔鼠血、脑组织测定相关指标。结果与正常对照组相比,高碘仔鼠血清和脑组织TT4显著下降,TT3水平亦降低;脑MBPmRNA表达水平较对照组下降了27%。补硒提高仔鼠甲状腺激素的水平,上调仔鼠脑MBPmRNA的表达。结论高碘引起仔鼠甲状腺激素水平降低是仔鼠脑MBPmRNA表达水平下降的原因,硒可通过影响含硒酶的活性来调节甲状腺激素水平从而上调仔鼠脑MBPmRNA的表达。

Effect of high-iodine intake on MBP mRNA expression in cerebrum of filial mice and selenium intervention

Objective To study the effect of selenium supplementation on myelin basic protein ~MBP) mRNA expression in cerebrum of high-iodine intake filial mice. Methods 135 weanling female Balb/C mice were assigned into 3 groups and given drinking water including different doses of iodine and selenium. Normal control ~NC, tap water), high iodine intake group ~HI, 3.0mg/L I of drinking water), high iodine intake and selenium supplementation group I ~HI Se, 3.0mg/L I 0.5mg/L Se of drinking water). All the male and female mice were mated after 4 months later, related indicators of filial mice on 14 day were determined. Results In filial mice, compared with NC group, serum TT_4 decreased significantly in HI groups, TT_3 also decreased, and mRNA expression of MBP in cerebrum was down-regulated 27%. The selenium suppleme ntation groups inhibited the decrease of TT_4 and TT_3, up regulated the m RNA expression of MBP in cerebrum. Conclusion High-iodine Intake can decrease thyroxine of filial mice, which maybe is the reason for down-regulated m RNA expression of MBP in cerebrum, and selenium can exert some intervention by thyroxine, but need to verify more.