摘要
目的初步探讨低硒、氧化应激和线粒体DNA D-Loop区突变三者之间的相关性。方法采用人工饲养的方法建立低硒小鼠模型,分为低硒30天、90天和正常组;原子吸收法检测肝脏硒含量;HE染色检测低硒对小鼠各脏器(心脏、肝脏、肾脏、脑)的病理形态学影响;基因芯片检测氧化还原酶类基因的表达并通过检测机体GSH-Px(谷胱甘肽过氧化物酶)、SOD(超氧化物歧化酶)和MDA(丙二醛)的含量进行机体抗氧化应激能力的检测;PCR-SSCP技术结合DNA测序筛选线粒体DNA D-Loop区的突变。结果成功建立低硒小鼠模型;低硒小鼠各脏器(心脏、肾脏、脑)均出现不同程度的病理形态学改变;低硒状态下机体处于高氧化应激状态,且随着低硒时间的延长机体的抗氧化状态减弱。在低硒组和对照组中均发现线粒体DNA D-Loop区存在一个多态性位点16 154位(A/T)rs33254715。结论低硒与单核苷酸多态性(single nucleotide polymorphism,SNP)位点:16 154(A/T)的发生并无直接联系,它既不随着低硒时间的延长而积累,也不存在组织特异性。
Abstract： Objective To study the correlation among selenium deficiency, oxidative stress and the mutation of mtDNA in different tissues （heart, kidney, liver and brain）. Methods Mice were fed a yeast-based, Se-deficient diet （0. 004 5μg/g） for 30 d and 90 d, respective- ly. The diet was deficient only in Se and received adequate doses of vitamins and other trace minerals. The levels of MDA, SOD, and the activities of GPx were investigated. The gene ex- pression profile associated with low Se status in the heart of C57B1/6J mice was analyzed and oxydoreductase mRNA levels in heart were determined using quantitative real time polymerase chain reaction analysis. Single strand conformation polymorphism （SSCP） and direct sequen- cing were used in screening and verifying the mutations in mt DNA. Results Selenium deft- ciency results in the significantly decreased expression of glutathione peroxidase 1 （ GPX-1 ） at mRNA levels. As compared with the control group, the levels of MDA and GSH-Px in selenium deficiency group were significantly decreased while the level of SOD was significantly in- creased. The SNP 16154（A/T） was found in both groups. The genotype frequencies and allele frequencies had no significant difference between selenium deficiency group and control group. Conclusion 16154 （A/T） is not associated with the concurrent of selenium deficiency direct- ly. SNP in the four tissues has no different matabolic and tissue specificity.
出处
《哈尔滨医科大学学报》
CAS
北大核心
2011年第6期505-509,共5页
Journal of Harbin Medical University
基金
国家自然科学基金资助项目(30771863)
哈尔滨市科技创新人才研究专项资金项目(2008RFXXS019)
关键词
低硒
氧化应激
线粒体DNA
单核苷酸多态性
selenium deficiency
oxidative stress
mitochondrial DNA
single nucleotide poly- morphism
